miscarriage

Some recommend not using the term "abortion" in discussions with those experiencing a miscarriage to decrease distress.{{cite book |last1=Greaves |first1=Ian |url=https://books.google.com/books?id=2Z3cMX7owGwC&pg=PA506 |title=Emergency Care: A Textbook for Paramedics |last2=Porter |first2=Keith |last3=Hodgetts |first3=Tim J. |last4=Woollard |first4=Malcolm |date=2005 |publisher=Elsevier Health Sciences |isbn=978-0-7020-2586-0 |location=London |page=506 |archive-url=https://web.archive.org/web/20160426205606/https://books.google.com/books?id=2Z3cMX7owGwC&pg=PA506 |archive-date=April 26, 2016 |url-status=live |df=mdy-all}} In Britain, the term "miscarriage" has replaced any use of the term "spontaneous abortion" for pregnancy loss and in response to complaints of insensitivity towards women who had suffered such loss.{{cite journal |vauthors=Moscrop A |date=1 December 2013 |title='Miscarriage or abortion?' Understanding the medical language of pregnancy loss in Britain; a historical perspective |journal=Medical Humanities |volume=39 |issue=2 |pages=98–104 |doi=10.1136/medhum-2012-010284 |pmc=3841747 |pmid=23429567 |doi-access=free}} An additional benefit of this change is reducing confusion among medical laymen, who may not realize that the term "spontaneous abortion" refers to a naturally occurring medical phenomenon and not the intentional termination of pregnancy.

The medical terminology applied to experiences during early pregnancy has changed over time.{{cite journal |vauthors=Moscrop A |date=December 2013 |title='Miscarriage or abortion?' Understanding the medical language of pregnancy loss in Britain; a historical perspective |journal=Medical Humanities |volume=39 |issue=2 |pages=98–104 |doi=10.1136/medhum-2012-010284 |pmc=3841747 |pmid=23429567}} Before the 1980s, health professionals used the phrase spontaneous abortion for a miscarriage and induced abortion for a termination of the pregnancy.{{cite journal |year=1988 |title=Standard terminology for reporting of reproductive health statistics in the United States |journal=Public Health Reports |volume=103 |issue=5 |pages=464–71 |pmc=1478116 |pmid=3140271}} By the 1940s, the popular assumption that an abortion was an intentional and immoral or criminal action was sufficiently ingrained that pregnancy books had to explain that abortion was the then-popular technical jargon for miscarriages.{{Cite news |last=Gross |first=Rachel E. |date=2024-08-13 |title=When 'Abortion' Wasn't a Dirty Word |url=https://www.nytimes.com/2024/08/13/science/medical-history-abortion.html |access-date=2024-08-15 |work=The New York Times |language=en-US |issn=0362-4331}}

In the 1960s, the use of the word miscarriage in Britain (instead of spontaneous abortion) occurred after changes in legislation. In the late 1980s and 1990s, doctors became more conscious of their language about early pregnancy loss. Some medical authors advocated a change to the use of miscarriage instead of spontaneous abortion because they argued this would be more respectful and help ease a distressing experience.{{cite journal |vauthors=Beard RW, Mowbray JF, Pinker GD |date=November 1985 |title=Miscarriage or abortion |journal=Lancet |volume=2 |issue=8464 |pages=1122–3 |doi=10.1016/S0140-6736(85)90709-3 |pmid=2865589 |s2cid=5163662}}{{cite journal |vauthors=Hutchon DJ, Cooper S |date=October 1998 |title=Terminology for early pregnancy loss must be changed |journal=BMJ |volume=317 |issue=7165 |pages=1081 |doi=10.1136/bmj.317.7165.1081 |pmc=1114078 |pmid=9774309}} The change was being recommended in Britain in the late 1990s. In 2005 the European Society for Human Reproduction and Embryology (ESHRE) published a paper aiming to facilitate a revision of nomenclature used to describe early pregnancy events.

Most affected women and family members refer to miscarriage as the loss of a baby, rather than an embryo or fetus, and healthcare providers are expected to respect and use the language that the person chooses. Clinical terms can suggest blame, increase distress, and even cause anger. Terms that are known to cause distress in those experiencing miscarriage include:

• abortion (including spontaneous abortion) rather than miscarriage,
• habitual aborter rather than a woman experiencing recurrent pregnancy loss,
• products of conception rather than baby,
• blighted ovum rather than early pregnancy loss or delayed miscarriage,
• cervical incompetence rather than cervical weakness, and
• evacuation of retained products of conception (ERPC) rather than surgical management of miscarriage.

Using the word abortion for an involuntary miscarriage is generally considered confusing, "a dirty word", "stigmatized", and "an all-around hated term".

Pregnancy loss is a broad term that is used for miscarriage, ectopic and molar pregnancies. The term foetal death applies variably in different countries and contexts, sometimes incorporating weight, and gestational age from 16 weeks in Norway, 20 weeks in the US and Australia, 24 weeks in the UK to 26 weeks in Italy and Spain.{{cite journal | vauthors = Mohangoo AD, Blondel B, Gissler M, Velebil P, Macfarlane A, Zeitlin J | title = International comparisons of fetal and neonatal mortality rates in high-income countries: should exclusion thresholds be based on birth weight or gestational age? | journal = PLOS ONE | volume = 8 | issue = 5 | pages = e64869 | year = 2013 | pmid = 23700489 | pmc = 3658983 | doi = 10.1371/journal.pone.0064869 | bibcode = 2013PLoSO...864869M | doi-access = free }}{{cite web| vauthors = Li Z, Zeki R, Hilder L, Sullivan EA |title=Australia's Mothers and Babies 2010|url=http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129542372|website=Perinatal statistics series no. 27. Cat. no. PER 57|publisher=Australian Institute of Health and Welfare National Perinatal Statistics Unit, Australian Government|access-date=4 July 2013|year=2012|url-status=live|archive-url=https://web.archive.org/web/20130718154709/http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129542372|archive-date=July 18, 2013|df=mdy-all}}{{cite web|author1=Royal College of Obstetricians |author2=Gynaecologists UK |title=Further Issues Relating to Late Abortion, Fetal Viability and Registration of Births and Deaths |url=http://www.rcog.org.uk/womens-health/clinical-guidance/further-issues-relating-late-abortion-fetal-viability-and-registrati |publisher=Royal College of Obstetricians and Gynaecologists UK |access-date=4 July 2013 |date=April 2001 |url-status=dead |archive-url=https://web.archive.org/web/20131105042348/http://www.rcog.org.uk/womens-health/clinical-guidance/further-issues-relating-late-abortion-fetal-viability-and-registrati |archive-date=November 5, 2013 }} A foetus that died before birth after this gestational age may be referred to as a stillbirth.

Signs of a miscarriage include vaginal spotting, abdominal pain, cramping, fluid, blood clots, and tissue passing from the vagina.{{cite web|url=https://www.nichd.nih.gov/health/topics/pregnancyloss/conditioninfo/Pages/diagnosed.aspx|title=How do health care providers diagnose pregnancy loss or miscarriage?|website=www.nichd.nih.gov|date=September 2017 |access-date=2017-11-07}}{{sfn|Hoffman|page=176}}{{cite journal | vauthors = Li L, Dou L, Leung PC, Wang CC | title = Chinese herbal medicines for threatened miscarriage | journal = The Cochrane Database of Systematic Reviews | issue = 5 | pages = CD008510 | date = May 2012 | pmid = 22592730 | doi = 10.1002/14651858.cd008510.pub2 | pmc = 11366073 }} Bleeding can be a symptom of miscarriage, but many women also have bleeding in early pregnancy and do not miscarry.{{cite news|url=https://medlineplus.gov/miscarriage.html|title=Miscarriage {{!}} Miscarriage Symptoms {{!}} MedlinePlus|access-date=2017-09-09|url-status=live|archive-url=https://web.archive.org/web/20170728020027/https://medlineplus.gov/miscarriage.html|archive-date=July 28, 2017|df=mdy-all}}{{PD-notice}} Bleeding during the first half of pregnancy may be referred to as a threatened miscarriage.{{cite journal | vauthors = Lee HJ, Norwitz E, Lee B | title = Relationship between threatened miscarriage and gestational diabetes mellitus | journal = BMC Pregnancy and Childbirth | volume = 18 | issue = 1 | pages = 318 | date = August 2018 | pmid = 30081861 | pmc = 6080503 | doi = 10.1186/s12884-018-1955-2 | doi-access = free }} Of those who seek treatment for bleeding during pregnancy, about half will miscarry.{{cite journal | vauthors = Everett C | title = Incidence and outcome of bleeding before the 20th week of pregnancy: prospective study from general practice | journal = BMJ | volume = 315 | issue = 7099 | pages = 32–4 | date = July 1997 | pmid = 9233324 | pmc = 2127042 | doi = 10.1136/bmj.315.7099.32 }} Miscarriage may be detected during an ultrasound exam or through serial human chorionic gonadotropin (HCG) testing.

{{Further|List of miscarriage risks}}

Miscarriage may occur for many reasons, not all of which can be identified. Risk factors are those things that increase the likelihood of having a miscarriage but do not necessarily cause a miscarriage. Up to 70 conditions,{{sfn|Hoffman|page=181–182}}{{cite journal | vauthors = Ali O, Hakimi I, Chanana A, Habib MA, Guelzim K, Kouach J, Rahali DM, Dehayeni M | title = [Term pegnancy on septate uterus: report of a case and review of the literature] | journal = The Pan African Medical Journal | volume = 22 | pages = 219 | date = 2015 | pmid = 26955410 | pmc = 4760728 | doi = 10.11604/pamj.2015.22.219.7790 }}{{cite journal | vauthors = Tersigni C, Castellani R, de Waure C, Fattorossi A, De Spirito M, Gasbarrini A, Scambia G, Di Simone N | title = Celiac disease and reproductive disorders: meta-analysis of epidemiologic associations and potential pathogenic mechanisms | journal = Human Reproduction Update | volume = 20 | issue = 4 | pages = 582–93 | year = 2014 | pmid = 24619876 | doi = 10.1093/humupd/dmu007 | doi-access = free | hdl = 10807/56796 | hdl-access = free }}{{sfn|Hoffman|page = 172}} infections,{{cite web |url=https://www.nhs.uk/conditions/miscarriage/causes/ |title=Miscarriage – Causes |author= |website=NHS |date=March 9, 2022 |url-status=live |archive-url=https://web.archive.org/web/20230705060654/https://www.nhs.uk/conditions/miscarriage/causes/ |archive-date=July 5, 2023}}{{cite journal | title = ACOG Practice Bulletin No.142: Cerclage for the management of cervical insufficiency | journal = Obstetrics and Gynecology | volume = 123 | issue = 2 Pt 1 | pages = 372–9 | date = February 2014 | pmid = 24451674 | doi = 10.1097/01.AOG.0000443276.68274.cc | author1 = American College of Obstetricians Gynecologists | s2cid = 205384229 }}{{cite journal | vauthors = Lis R, Rowhani-Rahbar A, Manhart LE | title = Mycoplasma genitalium infection and female reproductive tract disease: a meta-analysis | journal = Clinical Infectious Diseases | volume = 61 | issue = 3 | pages = 418–26 | date = August 2015 | pmid = 25900174 | doi = 10.1093/cid/civ312 | doi-access = free | hdl = 1773/26479 | hdl-access = free }} medical procedures,{{cite journal | vauthors = Tabor A, Alfirevic Z | title = Update on procedure-related risks for prenatal diagnosis techniques | journal = Fetal Diagnosis and Therapy | volume = 27 | issue = 1 | pages = 1–7 | year = 2010 | pmid = 20051662 | doi = 10.1159/000271995 | doi-access = free }}{{cite journal | vauthors = Agarwal K, Alfirevic Z | title = Pregnancy loss after chorionic villus sampling and genetic amniocentesis in twin pregnancies: a systematic review | journal = Ultrasound in Obstetrics & Gynecology | volume = 40 | issue = 2 | pages = 128–34 | date = August 2012 | pmid = 22125091 | doi = 10.1002/uog.10152 | s2cid = 23379631 }}{{cite journal | vauthors = Alfirevic Z, Navaratnam K, Mujezinovic F | title = Amniocentesis and chorionic villus sampling for prenatal diagnosis | journal = The Cochrane Database of Systematic Reviews | volume = 2017 | pages = CD003252 | date = September 2017 | issue = 9 | pmid = 28869276 | pmc = 6483702 | doi = 10.1002/14651858.cd003252.pub2 | publisher = John Wiley & Sons, Ltd | df = mdy-all }} lifestyle factors,{{cite journal | vauthors = Ness RB, Grisso JA, Hirschinger N, Markovic N, Shaw LM, Day NL, Kline J | title = Cocaine and tobacco use and the risk of spontaneous abortion | journal = The New England Journal of Medicine | volume = 340 | issue = 5 | pages = 333–9 | date = February 1999 | pmid = 9929522 | doi = 10.1056/NEJM199902043400501 | doi-access = free }}{{cite journal | vauthors = Venners SA, Wang X, Chen C, Wang L, Chen D, Guang W, Huang A, Ryan L, O'Connor J, Lasley B, Overstreet J, Wilcox A, Xu X | title = Paternal smoking and pregnancy loss: a prospective study using a biomarker of pregnancy | journal = American Journal of Epidemiology | volume = 159 | issue = 10 | pages = 993–1001 | date = May 2004 | pmid = 15128612 | doi = 10.1093/aje/kwh128 | doi-access = free }} occupational exposures,{{sfn|Hoffman|page=173}}{{sfn|Hoffman|page=272}} chemical exposure,{{sfn|Hoffman|page=272}} and shift work are associated with increased risk for miscarriage.{{cite journal | vauthors = Chavarro JE, Rich-Edwards JW, Gaskins AJ, Farland LV, Terry KL, Zhang C, Missmer SA | title = Contributions of the Nurses' Health Studies to Reproductive Health Research | journal = American Journal of Public Health | volume = 106 | issue = 9 | pages = 1669–76 | date = September 2016 | pmid = 27459445 | pmc = 4981818 | doi = 10.2105/AJPH.2016.303350 }}(review) Some of these risks include endocrine, genetic, uterine, or hormonal abnormalities, reproductive tract infections, and tissue rejection caused by an autoimmune disorder.{{cite journal | vauthors = Acién P, Acién M | title = The presentation and management of complex female genital malformations | journal = Human Reproduction Update | volume = 22 | issue = 1 | pages = 48–69 | date = 2016-01-01 | pmid = 26537987 | doi = 10.1093/humupd/dmv048 | doi-access = free }}

Most clinically apparent miscarriages (two-thirds to three-quarters in various studies) occur during the first trimester.{{cite web | last = Rosenthal | first = M. Sara | title = The Second Trimester | website = The Gynecological Sourcebook | publisher = WebMD | year = 1999 | url = http://www.webmd.com/content/article/4/1680_51802.htm | access-date = December 18, 2006 | url-status = live | archive-url = https://web.archive.org/web/20061201085538/http://www.webmd.com/content/article/4/1680_51802.htm | archive-date = December 1, 2006 | df = mdy-all }}{{cite book|title=Williams Obstetrics| vauthors = Cunningham F, Leveno KJ, Bloom SL, Spong CY, Dashe JS, Hoffman BL, Casey BM, Sheffield JS|publisher=McGraw-Hill|year=2013|pages=5|chapter=Abortion}} About 30% to 40% of all fertilised eggs miscarry, often before the pregnancy is known. The embryo typically dies before the pregnancy is expelled; bleeding into the decidua basalis and tissue necrosis cause uterine contractions to expel the pregnancy. Early miscarriages can be due to a developmental abnormality of the placenta or other embryonic tissues. In some instances, an embryo does not form but other tissues do. This has been called a "blighted ovum".{{cite news|url=http://americanpregnancy.org/pregnancy-complications/blighted-ovum/|title=Blighted Ovum: Symptoms, Causes and Prevention|date=2012-04-26|work=American Pregnancy Association|access-date=2017-09-09|language=en|url-status=live|archive-url=https://web.archive.org/web/20170725113127/http://americanpregnancy.org/pregnancy-complications/blighted-ovum/|archive-date=July 25, 2017|df=mdy-all}}{{cite news|url=http://www.mayoclinic.org/diseases-conditions/pregnancy-loss-miscarriage/expert-answers/blighted-ovum/faq-20057783|title=Blighted ovum: What causes it?|work=Mayo Clinic|access-date=2017-09-09|url-status=live|archive-url=https://web.archive.org/web/20170720141145/http://www.mayoclinic.org/diseases-conditions/pregnancy-loss-miscarriage/expert-answers/blighted-ovum/faq-20057783|archive-date=July 20, 2017|df=mdy-all}}{{sfn|Hoffman|page=171}}

Successful implantation of the zygote into the uterus is most likely eight to ten days after fertilization. If the zygote has not been implanted by day ten, implantation becomes increasingly unlikely in subsequent days.{{cite journal | vauthors = Wilcox AJ, Baird DD, Weinberg CR | title = Time of implantation of the conceptus and loss of pregnancy | journal = The New England Journal of Medicine | volume = 340 | issue = 23 | pages = 1796–9 | date = June 1999 | pmid = 10362823 | doi = 10.1056/NEJM199906103402304 | df = mdy-all | doi-access = free }}

A chemical pregnancy is a pregnancy that was detected by testing but ends in miscarriage before or around the time of the next expected period.{{cite book|editor1-last=Condous |editor1-first=George |editor2=Tom Bourne |date=2006 |title=Handbook of early pregnancy care |url=https://books.google.com/books?id=_Y3PyNvc6dcC&pg=PA28 |url-status=live |archive-url=https://web.archive.org/web/20170910181311/https://books.google.com/books?id=_Y3PyNvc6dcC&pg=PA29 |archive-date=September 10, 2017 |location=London |publisher=Informa Healthcare |isbn=978-0203016213 |pages=28–29 |df=mdy-all}}

Chromosomal abnormalities are found in more than half of embryos miscarried in the first 13 weeks. Half of embryonic miscarriages (25% of all miscarriages) have an aneuploidy (abnormal number of chromosomes).{{cite journal | vauthors = Kajii T, Ferrier A, Niikawa N, Takahara H, Ohama K, Avirachan S | title = Anatomic and chromosomal anomalies in 639 spontaneous abortuses | journal = Human Genetics | volume = 55 | issue = 1 | pages = 87–98 | year = 1980 | pmid = 7450760 | doi = 10.1007/BF00329132 | s2cid = 2133855 }} Common chromosome abnormalities found in miscarriages include an autosomal trisomy (22–32%), monosomy X (5–20%), triploidy (6–8%), tetraploidy (2–4%), or other structural chromosomal abnormalities (2%). Genetic problems are more likely to occur with older parents; this may account for the higher rates observed in older women.{{cite web | title = Pregnancy Over Age 30 | website=MUSC Children's Hospital | url = http://www.musckids.com/health_library/hrpregnant/over30.htm | access-date = December 18, 2006 |archive-url = https://web.archive.org/web/20061113233603/http://www.musckids.com/health_library/hrpregnant/over30.htm |archive-date = November 13, 2006}}

Luteal phase progesterone deficiency may or may not be a contributing factor to miscarriage.{{cite journal | vauthors = Bukulmez O, Arici A | title = Luteal phase defect: myth or reality | journal = Obstetrics and Gynecology Clinics of North America | volume = 31 | issue = 4 | pages = 727–44, ix | date = December 2004 | pmid = 15550332 | doi = 10.1016/j.ogc.2004.08.007 }}

Second-trimester losses may be due to maternal factors such as uterine malformation, growths in the uterus (fibroids), or cervical problems. These conditions also may contribute to premature birth. Unlike first-trimester miscarriages, second-trimester miscarriages are less likely to be caused by a genetic abnormality; chromosomal aberrations are found in a third of cases. Infection during the third trimester can cause a miscarriage.

Miscarriage is least common for mothers in their twenties, for whom around 12% of known pregnancies end in miscarriage. Risk rises with age: around 14% for women aged 30–34; 18% for those 35–39; 37% for those 40–44; and 65% for those over 45. Women younger than 20 have slightly increased miscarriage risk, with around 16% of known pregnancies ending in miscarriage.

Miscarriage risk also rises with paternal age, although the effect is less pronounced than for maternal age. The risk is lowest for men under 40 years old. For men aged 40-44, the risk is around 23% higher. For men over 45, the risk is 43% higher.{{cite journal |vauthors=Muncey W, Scott M, Lathi RB, Eisenberg ML |title=The paternal role in pregnancy loss |journal=Andrology |volume= |issue= |pages= |date=February 2024 |pmid=38334037 |doi=10.1111/andr.13603 |url=}}

Not only is obesity associated with miscarriage; it can result in sub-fertility and other adverse pregnancy outcomes. Recurrent miscarriage is also related to obesity. Women with bulimia nervosa and anorexia nervosa may have a greater risk for miscarriage. Nutrient deficiencies have not been found to impact miscarriage rates but hyperemesis gravidarum sometimes precedes a miscarriage.{{sfn|Hoffman|page=173}}

Caffeine consumption also has been correlated to miscarriage rates, at least at higher levels of intake. However, such higher rates are statistically significant only in certain circumstances.

Vitamin supplementation has generally not shown to be effective in preventing miscarriage.{{cite journal | vauthors = Balogun OO, da Silva Lopes K, Ota E, Takemoto Y, Rumbold A, Takegata M, Mori R | title = Vitamin supplementation for preventing miscarriage | journal = The Cochrane Database of Systematic Reviews | issue = 5 | pages = CD004073 | date = May 2016 | volume = 2016 | pmid = 27150280 | doi = 10.1002/14651858.cd004073.pub4 | pmc = 7104220 }} Chinese traditional medicine has not been found to prevent miscarriage.

Disorders of the thyroid may affect pregnancy outcomes. Related to this, iodine deficiency is strongly associated with an increased risk of miscarriage.{{sfn|Hoffman|page=173}} The risk of miscarriage is increased in those with poorly controlled insulin-dependent diabetes mellitus.{{sfn|Hoffman|page=173}} Women with well-controlled diabetes have the same risk of miscarriage as those without diabetes.{{cite book|author=Fred F. Ferri|title=Ferri's Clinical Advisor 2017|url=https://books.google.com/books?id=rRhCDAAAQBAJ&pg=PA1198|year=2017|publisher=Elsevier|isbn=978-0-323-28048-8|page=1198}}{{cite book|author1=Sumita Mehta|author2=Bindiya Gupta|title=Recurrent Pregnancy Loss|url=https://books.google.com/books?id=5KZWDwAAQBAJ&pg=PA185|year=2018|publisher=Springer|isbn=978-981-10-7337-3|page=185}}

Ingesting food that has been contaminated with listeriosis, toxoplasmosis, and salmonella is associated with an increased risk of miscarriage.

Amniocentesis and chorionic villus sampling (CVS) are procedures conducted to assess the fetus. A sample of amniotic fluid is obtained by the insertion of a needle through the abdomen and into the uterus. Chorionic villus sampling is a similar procedure with a sample of tissue removed rather than fluid. These procedures are not associated with pregnancy loss during the second trimester but they are associated with miscarriages and birth defects in the first trimester. Miscarriage caused by invasive prenatal diagnosis (chorionic villus sampling (CVS) and amniocentesis) is rare (about 1%).

The effects of surgery on pregnancy are not well-known including the effects of bariatric surgery. Abdominal and pelvic surgery are not risk factors for miscarriage. Ovarian tumours and cysts that are removed have not been found to increase the risk of miscarriage. The exception to this is the removal of the corpus luteum from the ovary. This can cause fluctuations in the hormones necessary to maintain the pregnancy.{{sfn|Hoffman|pages=172–173}}

There is no significant association between antidepressant medication exposure and miscarriage.{{cite journal | vauthors = Ross LE, Grigoriadis S, Mamisashvili L, Vonderporten EH, Roerecke M, Rehm J, Dennis CL, Koren G, Steiner M, Mousmanis P, Cheung A | title = Selected pregnancy and delivery outcomes after exposure to antidepressant medication: a systematic review and meta-analysis | journal = JAMA Psychiatry | volume = 70 | issue = 4 | pages = 436–43 | date = April 2013 | pmid = 23446732 | doi = 10.1001/jamapsychiatry.2013.684 | doi-access = | s2cid = 2065578 }} The risk of miscarriage is not likely decreased by discontinuing SSRIs before pregnancy.{{cite journal | vauthors = Dalke KB, Wenzel A, Kim DR | title = Depression and Anxiety During Pregnancy: Evaluating the Literature in Support of Clinical Risk-Benefit Decision-Making | journal = Current Psychiatry Reports | volume = 18 | issue = 6 | pages = 59 | date = June 2016 | pmid = 27091646 | doi = 10.1007/s11920-016-0698-x | s2cid = 984767 }} Some available data suggest that there is a small increased risk of miscarriage for women taking any antidepressant,{{cite journal | vauthors = Broy P, Bérard A | title = Gestational exposure to antidepressants and the risk of spontaneous abortion: a review | journal = Current Drug Delivery | volume = 7 | issue = 1 | pages = 76–92 | date = January 2010 | pmid = 19863482 | doi = 10.2174/156720110790396508 }}{{cite journal | vauthors = Nakhai-Pour HR, Broy P, Bérard A | title = Use of antidepressants during pregnancy and the risk of spontaneous abortion | journal = CMAJ | volume = 182 | issue = 10 | pages = 1031–7 | date = July 2010 | pmid = 20513781 | pmc = 2900326 | doi = 10.1503/cmaj.091208 }} though this risk becomes less statistically significant when excluding studies of poor quality.{{cite journal | vauthors = Yonkers KA, Blackwell KA, Glover J, Forray A | title = Antidepressant use in pregnant and postpartum women | journal = Annual Review of Clinical Psychology | volume = 10 | issue = 1 | pages = 369–92 | date = 2014-01-01 | pmid = 24313569 | pmc = 4138492 | doi = 10.1146/annurev-clinpsy-032813-153626 }}

Medicines that increase the risk of miscarriage include:

• retinoids
• nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen
• misoprostol
• methotrexate
• statins{{cite journal | vauthors = Grundy SM, Stone NJ, Bailey AL, Beam C, Birtcher KK, Blumenthal RS, Braun LT, de Ferranti S, Faiella-Tommasino J, Forman DE, Goldberg R, Heidenreich PA, Hlatky MA, Jones DW, Lloyd-Jones D, Lopez-Pajares N, Ndumele CE, Orringer CE, Peralta CA, Saseen JJ, Smith SC, Sperling L, Virani SS, Yeboah J | title = 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA Guideline on the Management of Blood Cholesterol: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines | journal = Journal of the American College of Cardiology | volume = 73 | issue = 24 | pages = 3168–3209 | date = June 2019 | pmid = 30423391 | doi = 10.1016/j.jacc.2018.11.002 | doi-access = free }}

Immunisations have not been found to cause miscarriage.{{sfn|Hoffman|page=72}} Live vaccinations, like the MMR vaccine, can theoretically cause damage to the fetus as the live virus can cross the placenta and potentially increase the risk for miscarriage.{{cite journal | vauthors = Racicot K, Mor G | title = Risks associated with viral infections during pregnancy | journal = The Journal of Clinical Investigation | volume = 127 | issue = 5 | pages = 1591–1599 | date = May 2017 | pmid = 28459427 | pmc = 5409792 | doi = 10.1172/JCI87490 }}{{cite journal | vauthors = Bozzo P, Narducci A, Einarson A | title = Vaccination during pregnancy | journal = Canadian Family Physician | volume = 57 | issue = 5 | pages = 555–7 | date = May 2011 | pmid = 21571717 | pmc = 3093587 }} Therefore, the Center for Disease Control (CDC) recommends against pregnant women receiving live vaccinations.{{cite web|url=https://www.cdc.gov/vaccines/pregnancy/hcp-toolkit/guidelines.html|title=Pregnancy Guidelines and Recommendations by Vaccine {{!}} CDC|date=2019-04-19|website=www.cdc.gov|access-date=2019-08-01}} However, there is no clear evidence that has shown live vaccinations increase the risk of miscarriage or fetal abnormalities.

Some live vaccinations include: MMR, varicella, certain types of the influenza vaccine, and rotavirus.{{cite web|url=https://www.cdc.gov/vaccines/vpd/vaccines-list.html|title=List of Vaccines {{!}} CDC|date=2019-04-15|website=www.cdc.gov|language=en-us|access-date=2019-08-06}}{{cite web|url=https://www.vaccines.gov/basics/types|title=Vaccine Types {{!}} Vaccines|website=www.vaccines.gov|access-date=2019-08-06}}

Ionising radiation levels given to a woman during cancer treatment cause miscarriage. Exposure can also impact fertility. The use of chemotherapeutic drugs to treat childhood cancer increases the risk of future miscarriage.{{sfn|Hoffman|page=173}}

Several pre-existing diseases in pregnancy can potentially increase the risk of miscarriage, including diabetes, endometriosis, polycystic ovary syndrome (PCOS), hypothyroidism, certain infectious diseases, and autoimmune diseases.

Women with endometriosis report a 76%{{cite web |last1=Saraswat |first1=Lucky |title=ESHRE2015: Endometriosis associated with a greater risk of complications in pregnancy |url=https://endometriosis.org/news/congress-highlights/eshre2015-endometriosis-associated-with-a-greater-risk-of-complications-in-pregnancy/#:~:text=After%20adjustments%20for%20age%20and%20previous%20pregnancy%2C%20results,three%20times%20higher%20for%20ectopic%20pregnancy%20%28OR%202.7%29 |website=endometriosis.org |publisher=European Society of Human Reproduction and Embryology |access-date=14 February 2024 |date=2015}} to 298%{{cite journal |last1=Schliep |first1=Karen C |last2=Farland |first2=Leslie V |last3=Pollack |first3=Anna Z |last4=Louis |first4=Germaine Buck |last5=Stanford |first5=Joseph B |last6=Allen-Brady |first6=Kristina |last7=Varner |first7=Michael W |last8=Kah |first8=Kebba |last9=Peterson |first9=C Matthew |title=Endometriosis diagnosis, staging and typology and adverse pregnancy outcome history |journal=Paediatric and Perinatal Epidemiology |date=November 2022 |volume=36 |issue=6 |pages=771–781 |doi=10.1111/ppe.12887 |pmid=35570746 |pmc=9588543}} increase in miscarriages versus their non-afflicted peers, the range affected by the severity of their disease. PCOS may increase the risk of miscarriage. Two studies suggested treatment with the drug metformin significantly lowers the rate of miscarriage in women with PCOS,{{cite journal | vauthors = Jakubowicz DJ, Iuorno MJ, Jakubowicz S, Roberts KA, Nestler JE | title = Effects of metformin on early pregnancy loss in the polycystic ovary syndrome | journal = The Journal of Clinical Endocrinology and Metabolism | volume = 87 | issue = 2 | pages = 524–9 | date = February 2002 | pmid = 11836280 | doi = 10.1210/jcem.87.2.8207 | doi-access = free }}{{cite journal | vauthors = Khattab S, Mohsen IA, Foutouh IA, Ramadan A, Moaz M, Al-Inany H | title = Metformin reduces abortion in pregnant women with polycystic ovary syndrome | journal = Gynecological Endocrinology | volume = 22 | issue = 12 | pages = 680–4 | date = December 2006 | pmid = 17162710 | doi = 10.1080/09513590601010508 | s2cid = 41735428 }} but the quality of these studies has been questioned.{{cite web|last=Royal College of Obstetricians and Gynaecologists|title=Long-term consequences of polycystic ovarian syndrome|url=http://www.rcog.org.uk/files/rcog-corp/uploaded-files/GT33_LongTermPCOS.pdf|archive-url=https://web.archive.org/web/20090413130238/http://www.rcog.org.uk/files/rcog-corp/uploaded-files/GT33_LongTermPCOS.pdf|url-status=dead|archive-date=2009-04-13|website=Green-top Guideline No. 27|publisher=Royal College of Obstetricians and Gynaecologists|access-date=2 July 2013|date=December 2007}} Metformin treatment in pregnancy is not safe.{{cite journal | vauthors = Lilja AE, Mathiesen ER | title = Polycystic ovary syndrome and metformin in pregnancy | journal = Acta Obstetricia et Gynecologica Scandinavica | volume = 85 | issue = 7 | pages = 861–8 | year = 2006 | pmid = 16817087 | doi = 10.1080/00016340600780441 | s2cid = 42002774 | doi-access = free }} In 2007, the Royal College of Obstetricians and Gynaecologists also recommended against the use of the drug to prevent miscarriage. Thrombophilias or defects in coagulation and bleeding were once thought to be a risk of miscarriage but have been subsequently questioned.{{sfn|Hoffman|page=174}} Severe cases of hypothyroidism increase the risk of miscarriage. The effect of milder cases of hypothyroidism on miscarriage rates has not been established. A condition called luteal phase defect (LPD) is a failure of the uterine lining to be fully prepared for pregnancy. This can keep a fertilised egg from implanting or result in miscarriage.{{cite web|url=https://www.womenshealth.gov/pregnancy/you-get-pregnant/trying-conceive/#4|title=Trying to conceive {{!}} womenshealth.gov|website=womenshealth.gov|access-date=2017-09-11|date=December 13, 2016}}{{PD-notice}}

Mycoplasma genitalium infection is associated with an increased risk of preterm birth and miscarriage.

Infections can increase the risk of a miscarriage: rubella (German measles), cytomegalovirus, bacterial vaginosis, HIV, chlamydia, gonorrhoea, syphilis, and malaria.

Autoimmunity is a possible cause of recurrent or late-term miscarriages. In the case of an autoimmune-induced miscarriage, the woman's body attacks the growing fetus or prevents normal pregnancy progression.{{cite journal | vauthors = Carp HJ, Selmi C, Shoenfeld Y | title = The autoimmune bases of infertility and pregnancy loss | journal = Journal of Autoimmunity | volume = 38 | issue = 2–3 | pages = J266-74 | date = May 2012 | pmid = 22284905 | doi = 10.1016/j.jaut.2011.11.016 | type = Review }}{{cite journal|year=2007|title=Female infertility due to abnormal autoimmunity: Frequently overlooked and greatly underappreciated. Part II|journal=Expert Review of Obstetrics & Gynecology|volume=2|issue=4|pages=465–75|doi=10.1586/17474108.2.4.465|vauthors=Gleicher N, Weghofer A, Barad D}} Autoimmune disease may cause abnormalities in embryos, which in turn may lead to miscarriage. As an example, coeliac disease increases the risk of miscarriage by an odds ratio of approximately 1.4.{{sfn|Hoffman|page = 172}} A disruption in normal immune function can lead to the formation of antiphospholipid antibody syndrome. This will affect the ability to continue the pregnancy, and if a woman has repeated miscarriages, she can be tested for it.{{sfn|Hoffman|page=272}} Approximately 15% of recurrent miscarriages are related to immunologic factors.{{sfn|Hoffman|page=182}} The presence of anti-thyroid autoantibodies is associated with an increased risk with an odds ratio of 3.73 and 95% confidence interval 1.8–7.6.{{cite journal | vauthors = van den Boogaard E, Vissenberg R, Land JA, van Wely M, van der Post JA, Goddijn M, Bisschop PH | title = Significance of (sub)clinical thyroid dysfunction and thyroid autoimmunity before conception and in early pregnancy: a systematic review | journal = Human Reproduction Update | volume = 17 | issue = 5 | pages = 605–19 | year = 2011 | pmid = 21622978 | doi = 10.1093/humupd/dmr024 | doi-access = }} Having lupus also increases the risk of miscarriage.{{cite web|url=https://www.womenshealth.gov/lupus/pregnancy-and-lupus|title=Pregnancy and lupus|website=womenshealth.gov|access-date=2017-09-11|date=April 20, 2017}} Immunohistochemical studies on decidual basalis and chorionic villi found that the imbalance of the immunological environment could be associated with recurrent pregnancy loss.{{cite journal | last1=Kavvadas | first1=Dimitrios | last2=Karachrysafi | first2=Sofia | last3=Anastasiadou | first3=Pinelopi | last4=Kavvada | first4=Asimoula | last5=Fotiadou | first5=Stella | last6=Papachristodoulou | first6=Angeliki | last7=Papamitsou | first7=Theodora | last8=Sioga | first8=Antonia | title=Immunohistochemical Evaluation of CD3, CD4, CD8, and CD20 in Decidual and Trophoblastic Tissue Specimens of Patients with Recurrent Pregnancy Loss | journal=Clinics and Practice | publisher=MDPI AG | volume=12 | issue=2 | date=2022-02-28 | issn=2039-7283 | doi=10.3390/clinpract12020022 | pages=177–193 |pmid=35314592 |pmc=8938768 | doi-access=free }}

Fifteen per cent of women who have experienced three or more recurring miscarriages have some anatomical defect that prevents the pregnancy from being carried for the entire term.{{sfn|Hoffman|page=181}} The structure of the uterus affects the ability to carry a child to term. Anatomical differences are common and can be congenital.{{Cite journal |last1=Qian |first1=Liang |last2=Ding |first2=Jiashan |last3=Shi |first3=Lan |last4=Yu |first4=Qing |last5=Zhu |first5=Jiawei |last6=Huang |first6=Anfeng |date=2023-12-04 |title=Analysis of hemi-uterus pregnancy outcomes in uterine malformations: a retrospective observational study |journal=BMC Pregnancy and Childbirth |volume=23 |issue=1 |pages=836 |doi=10.1186/s12884-023-06136-w |doi-access=free |pmid=38049742 |pmc=10696795 |issn=1471-2393}}

In some women, cervical incompetence or cervical insufficiency occurs with the inability of the cervix to stay closed during the entire pregnancy. It does not cause first-trimester miscarriages. In the second trimester, it is associated with an increased risk of miscarriage. It is identified after a premature birth has occurred at about 16–18 weeks into the pregnancy.{{sfn|Hoffman|page=181}} During the second trimester, major trauma can result in a miscarriage.{{sfn|Hoffman|page=172}}

{{See also|Smoking and pregnancy}}

Tobacco (cigarette) smokers have an increased risk of miscarriage. There is an increased risk regardless of which parent smokes, though the risk is higher when the gestational mother smokes.

Nausea and vomiting of pregnancy (NVP, or morning sickness) are associated with a decreased risk. Several possible causes have been suggested for morning sickness but there is still no agreement.{{cite journal | vauthors = Koren G | title = Treating morning sickness in the United States--changes in prescribing are needed | journal = American Journal of Obstetrics and Gynecology | volume = 211 | issue = 6 | pages = 602–6 | date = December 2014 | pmid = 25151184 | doi = 10.1016/j.ajog.2014.08.017 | doi-access = }} NVP may represent a defence mechanism which discourages the mother's ingestion of foods that are harmful to the fetus; according to this model, a lower frequency of miscarriage would be an expected consequence of the different food choices made by women experiencing NVP.{{cite book|chapter-url=https://books.google.com/books?id=FPgWDAAAQBAJ&q=nausea+vomiting+pregnancy+defense+mechanism+2017&pg=PA310|title=Anthropology: The Human Challenge|last1=Haviland|first1=William A.|last2=Prins|first2=Harald E. L.|last3=Walrath|last4=McBride|first4=Bunny |date=2016|publisher=Cengage Learning|isbn=978-1305863354|pages=31|chapter=12. Human Adaptation to Changing World}}

Chemical and occupational exposures may have some effect on pregnancy outcomes.{{cite journal | vauthors = Snijder CA, Roeleveld N, Te Velde E, Steegers EA, Raat H, Hofman A, Jaddoe VW, Burdorf A | title = Occupational exposure to chemicals and fetal growth: the Generation R Study | journal = Human Reproduction | volume = 27 | issue = 3 | pages = 910–20 | date = March 2012 | pmid = 22215632 | pmc = 3279127 | doi = 10.1093/humrep/der437 }} A cause-and-effect relationship can rarely be established. Those chemicals that are implicated in increasing the risk for miscarriage are DDT, lead,{{cite journal | vauthors = Krieg SA, Shahine LK, Lathi RB | title = Environmental exposure to endocrine-disrupting chemicals and miscarriage | journal = Fertility and Sterility | volume = 106 | issue = 4 | pages = 941–7 | date = September 2016 | pmid = 27473347 | doi = 10.1016/j.fertnstert.2016.06.043 | doi-access = free }} formaldehyde, arsenic, benzene and ethylene oxide. Video display terminals and ultrasound have not been found to affect the rates of miscarriage. In dental offices where nitrous oxide is used with the absence of anaesthetic gas scavenging equipment, there is a greater risk of miscarriage. For women who work with cytotoxic antineoplastic chemotherapeutic agents, there is a small increased risk of miscarriage. No increased risk for cosmetologists has been found.{{sfn|Hoffman|page=272}}

Alcohol increases the risk of miscarriage. Cocaine use increases the rate of miscarriage. Some infections have been associated with miscarriage. These include Ureaplasma urealyticum, Mycoplasma hominis, group B streptococci, HIV-1, and syphilis. Chlamydia trachomatis may increase the risk of miscarriage. Toxoplasmosis can cause a miscarriage.{{cite web |author= |date=September 10, 2020 |title=Toxoplasmosis |url=https://www.nhs.uk/conditions/toxoplasmosis/ |website=NHS |url-status=live |archive-url=https://web.archive.org/web/20230612022939/https://www.nhs.uk/conditions/toxoplasmosis/ |archive-date=June 12, 2023}} Subclinical infections of the lining of the womb, commonly known as chronic endometritis, are also associated with poor pregnancy outcomes, compared to women with treated chronic endometritis or no chronic endometritis.Rimmer MP, Fishwick K, Henderson I, Chinn D, Al Wattar BH and Quenby S. Quantifying CD138+ cells in the endometrium to assess chronic endometritis in women at risk of recurrent pregnancy loss: A prospective cohort study and rapid review. J Obstet Gynaecol Res. 2020.

In the case of blood loss, pain, or both, transvaginal ultrasound is performed. If a viable intrauterine pregnancy is not found with ultrasound, blood tests (serial βHCG tests) can be performed to rule out ectopic pregnancy, which is a life-threatening situation.{{cite journal | vauthors = Condous G, Okaro E, Khalid A, Bourne T | title = Do we need to follow up complete miscarriages with serum human chorionic gonadotrophin levels? | journal = BJOG | volume = 112 | issue = 6 | pages = 827–9 | date = June 2005 | pmid = 15924545 | doi = 10.1111/j.1471-0528.2004.00542.x | s2cid = 7546943 }}{{cite web|url=http://us.bestpractice.bmj.com/best-practice/monograph/666.html|title=Miscarriage|last=BMJ Best Practice|website=us.bestpractice.bmj.com|others=Ida Muslim, Jothi Doraiswamy, Acknowledgements|access-date=2017-10-08}}

If hypotension, tachycardia, and anaemia are discovered, the exclusion of an ectopic pregnancy is important.

A miscarriage may be confirmed by an obstetric ultrasound and by the examination of the passed tissue. When looking for microscopic pathologic symptoms, one looks for the products of conception. Microscopically, these include villi, trophoblast, fetal parts, and background gestational changes in the endometrium. When chromosomal abnormalities are found in more than one miscarriage, genetic testing of both parents may be done.{{cite web|url=http://www.rcog.org.uk/files/rcog-corp/GTG17recurrentmiscarriage.pdf|archive-url=https://web.archive.org/web/20130705172612/https://www.rcog.org.uk/files/rcog-corp/GTG17recurrentmiscarriage.pdf |archive-date=July 5, 2013|title=The investigation and treatment of couples with recurrent first-trimester and second-trimester miscarriage |last=Royal College of Obstetricians and Gynaecologists (RCOG) |date=April 2011 |publisher=Royal College of Obstetricians and Gynaecologists (RCOG) |website=Green-top Guideline No. 17 |access-date=2 July 2013 }}

A review article in The New England Journal of Medicine based on a consensus meeting of the Society of Radiologists in Ultrasound in America (SRU) has suggested that miscarriage should be diagnosed only if any of the following criteria are met upon ultrasonography visualisation:{{cite journal | vauthors = Doubilet PM, Benson CB, Bourne T, Blaivas M, Barnhart KT, Benacerraf BR, Brown DL, Filly RA, Fox JC, Goldstein SR, Kendall JL, Lyons EA, Porter MB, Pretorius DH, Timor-Tritsch IE | title = Diagnostic criteria for nonviable pregnancy early in the first trimester | journal = The New England Journal of Medicine | volume = 369 | issue = 15 | pages = 1443–51 | date = October 2013 | pmid = 24106937 | doi = 10.1056/NEJMra1302417 | url = https://escholarship.org/uc/item/3g86q83k }}

A threatened miscarriage is any bleeding during the first half of pregnancy. At the investigation, it may be found that the foetus remains viable and the pregnancy continues without further problems.{{Medical citation needed|date=November 2017}}

An anembryonic pregnancy (also called an "empty sac" or "blighted ovum") is a condition where the gestational sac develops normally, while the embryonic part of the pregnancy is either absent or stops growing very early. This accounts for approximately half of miscarriages. All other miscarriages are classified as embryonic miscarriages, meaning that there is an embryo present in the gestational sac. Half of embryonic miscarriages have aneuploidy (an abnormal number of chromosomes).

An inevitable miscarriage occurs when the cervix has already dilated,{{cite book |first1=Latha |last1=Stead |first2=S. Matthew |last2=Stead |first3=Matthew |last3=Kaufman|first4=Luis |last4=Suarez |title=First Aid for The Obstetrics and Gynecology Clerkship |url=https://archive.org/details/maxwellquickmedi00stea |url-access=limited |publisher=McGraw-Hill|location=New York |year=2006 |page=[https://archive.org/details/maxwellquickmedi00stea/page/n136 138] |isbn=978-0-07-144874-1}} but the foetus has yet to be expelled. This usually will progress to a complete miscarriage. The foetus may or may not have cardiac activity.

File:Complete miscarriage.jpg after an episode of heavy bleeding in an intrauterine pregnancy that had been confirmed by previous ultrasonography. There is some widening between the uterine walls, but no sign of any gestational sac, thus, in this case, being diagnostic of a complete miscarriage.]] A complete miscarriage is when all products of conception have been expelled; these may include the trophoblast, chorionic villi, gestational sac, yolk sac, and fetal pole (embryo); or later in the pregnancy the foetus, umbilical cord, placenta, amniotic fluid, and amniotic membrane. The presence of a pregnancy test that is still positive, as well as an empty uterus upon transvaginal ultrasonography, does, however, fulfil the definition of pregnancy of unknown location. Therefore, there may be a need for follow-up pregnancy tests to ensure that there is no remaining pregnancy, including ectopic pregnancy.{{Citation needed|date=May 2019}}

File:Incomplete miscarriage.jpg, with some products of conception in the cervix (to the left in the image) and remnants of a gestational sac by the fundus (to the right in the image), indicating an incomplete miscarriage]]

An incomplete miscarriage occurs when some products of conception have been passed, but some remain inside the uterus.{{cite web |author=MedlinePlus | author-link =MedlinePlus | date = October 25, 2004 |url=https://www.nlm.nih.gov/medlineplus/ency/article/000904.htm | title =Abortion – incomplete | website=Medical Encyclopedia| access-date =May 24, 2006 |archive-url =https://web.archive.org/web/20060425090648/https://www.nlm.nih.gov/medlineplus/ency/article/000904.htm |archive-date = April 25, 2006}} However, an increased distance between the uterine walls on transvaginal ultrasonography may also simply be an increased endometrial thickness and/or a polyp. The use of a Doppler ultrasound may be better in confirming the presence of significant retained products of conception in the uterine cavity.{{cite journal | vauthors = Kirk E, Bottomley C, Bourne T | title = Diagnosing ectopic pregnancy and current concepts in the management of pregnancy of unknown location | journal = Human Reproduction Update | volume = 20 | issue = 2 | pages = 250–61 | year = 2013 | pmid = 24101604 | doi = 10.1093/humupd/dmt047 | doi-access = }} In cases of uncertainty, ectopic pregnancy must be excluded using techniques like serial beta-hCG measurements.File:Delayed or missed miscarriage at 13 weeks.gifA missed miscarriage is when the embryo or fetus has died, but a miscarriage has not yet occurred. It is also referred to as delayed miscarriage, silent miscarriage, or missed abortion.{{cite journal |author4=ESHRE Special Interest Group for Early Pregnancy |vauthors=Farquharson RG, Jauniaux E, Exalto N |date=November 2005 |title=Updated and revised nomenclature for description of early pregnancy events |journal=Human Reproduction |volume=20 |issue=11 |pages=3008–11 |doi=10.1093/humrep/dei167 |pmid=16006453 |doi-access=free}}{{cite journal | vauthors = Hutchon DJ | title = Missed abortion versus delayed miscarriage | journal = British Journal of Obstetrics and Gynaecology | volume = 104 | issue = 6 | pages = 753 | date = June 1997 | pmid = 9197887 | doi = 10.1111/j.1471-0528.1997.tb11994.x | s2cid = 27778591 | doi-access = }}

A septic miscarriage occurs when the tissue from a missed or incomplete miscarriage becomes infected, which carries the risk of spreading infection (sepsis) and can be fatal.

Recurrent miscarriage ("recurrent pregnancy loss" (RPL), "recurrent spontaneous abortion (RSA), or "habitual abortion") is the occurrence of multiple consecutive miscarriages; the exact number used to diagnose recurrent miscarriage varies; however, two is the minimum threshold to meet the criteria.{{cite journal |last1=Paz Levy |first1=Dorit |last2=Wainstock |first2=Tamar |last3=Sheiner |first3=Eyal |last4=Sergienko |first4=Ruslan |last5=Landau |first5=Daniella |last6=Walfisch |first6=Asnat |date=2019-01-01 |title=Maternal recurrent pregnancy loss is associated with an increased risk for long-term neurological morbidity in offspring |journal=Developmental Medicine & Child Neurology |language=en |volume=61 |issue=1 |pages=91–97 |doi=10.1111/dmcn.13976 |pmid=30058166 |s2cid=51863388 |issn=0012-1622|doi-access=free }} If the proportion of pregnancies ending in miscarriage is 15% and assuming that miscarriages are independent events, then the probability of two consecutive miscarriages is 2.25% and the probability of three consecutive miscarriages is 0.34%. The occurrence of recurrent pregnancy loss is 1%.{{cite web |author=Royal College of Obstetricians and Gynaecologists |author-link=Royal College of Obstetricians and Gynaecologists |date=May 2003 |title=The investigation and treatment of couples with recurrent miscarriage |website=Green-top Guideline No. 17 |url=http://www.rcog.org.uk/womens-health/clinical-guidance/investigation-and-treatment-couples-recurrent-miscarriage-green-top- |access-date=October 20, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20110104235744/http://www.rcog.org.uk/womens-health/clinical-guidance/investigation-and-treatment-couples-recurrent-miscarriage-green-top- |archive-date=January 4, 2011 |df=mdy-all }} A large majority (85%) of those who have had two miscarriages will conceive and carry normally afterward.

The physical symptoms of a miscarriage vary according to the length of pregnancy, though most miscarriages cause pain or cramping. The size of blood clots and pregnancy tissue that are passed becomes larger with longer gestations. After 13 weeks' gestation, there is a higher risk of placenta retention.{{cite web | date=October 2004| title=Miscarriage: Emotional considerations and support | url=http://www.birth.com.au/Info.asp?class=6620&page=13| access-date=3 January 2014 | url-status=dead| archive-url=https://web.archive.org/web/20081201112940/http://www.birth.com.au/Info.asp?class=6620&page=13| archive-date=December 1, 2008 |publisher=Birth.com.au |page=13 | df=mdy-all}}

Prevention of a miscarriage can sometimes be accomplished by decreasing risk factors. This may include good prenatal care, avoiding drugs and alcohol, preventing infectious diseases, and avoiding X-rays. Identifying the cause of the miscarriage may help prevent future pregnancy loss, especially in cases of recurrent miscarriage. Often, there is little a person can do to prevent a miscarriage. Vitamin supplementation before or during pregnancy has not been found to affect the risk of miscarriage.{{cite journal | vauthors = Balogun OO, da Silva Lopes K, Ota E, Takemoto Y, Rumbold A, Takegata M, Mori R | title = Vitamin supplementation for preventing miscarriage | journal = The Cochrane Database of Systematic Reviews | volume = 2016 | issue = 5 | pages = CD004073 | date = May 2016 | pmid = 27150280 | doi = 10.1002/14651858.CD004073.pub4 | df = mdy-all | pmc = 7104220 }} Progesterone has been shown to prevent miscarriage in women with 1) vaginal bleeding early in their current pregnancy and 2) a previous history of miscarriage.{{cite journal|url=https://www.journalslibrary.nihr.ac.uk/hta/hta24330/#/full-report|doi = 10.3310/hta24330|title = Progesterone to prevent miscarriage in women with early pregnancy bleeding: The PRISM RCT|year = 2020|last1 = Coomarasamy|first1 = Arri|last2 = Harb|first2 = Hoda M.|last3 = Devall|first3 = Adam J.|last4 = Cheed|first4 = Versha|last5 = Roberts|first5 = Tracy E.|last6 = Goranitis|first6 = Ilias|last7 = Ogwulu|first7 = Chidubem B.|last8 = Williams|first8 = Helen M.|last9 = Gallos|first9 = Ioannis D.|last10 = Eapen|first10 = Abey|last11 = Daniels|first11 = Jane P.|last12 = Ahmed|first12 = Amna|last13 = Bender-Atik|first13 = Ruth|last14 = Bhatia|first14 = Kalsang|last15 = Bottomley|first15 = Cecilia|last16 = Brewin|first16 = Jane|last17 = Choudhary|first17 = Meenakshi|last18 = Crosfill|first18 = Fiona|last19 = Deb|first19 = Shilpa|last20 = Duncan|first20 = W Colin|last21 = Ewer|first21 = Andrew|last22 = Hinshaw|first22 = Kim|last23 = Holland|first23 = Thomas|last24 = Izzat|first24 = Feras|last25 = Johns|first25 = Jemma|last26 = Lumsden|first26 = Mary-Ann|last27 = Manda|first27 = Padma|last28 = Norman|first28 = Jane E.|last29 = Nunes|first29 = Natalie|last30 = Overton|first30 = Caroline E.|journal = Health Technology Assessment|volume = 24|issue = 33|pages = 1–70|pmid = 32609084|pmc = 7355406}}

Preventing a miscarriage in subsequent pregnancies may be enhanced with assessments of:

{{div col|colwidth=30em}}

• Immune status
• Chemical and occupational exposures{{sfn|Hoffman|page=272|}}
• Anatomical defects{{sfn|Hoffman|page=181|}}
• Pre-existing or acquired disease in pregnancy{{sfn|Hoffman|page=174|}}
• Polycystic ovary syndrome{{cite journal | vauthors = Boomsma CM, Fauser BC, Macklon NS | title = Pregnancy complications in women with polycystic ovary syndrome | journal = Seminars in Reproductive Medicine | volume = 26 | issue = 1 | pages = 72–84 | date = January 2008 | pmid = 18181085 | doi = 10.1055/s-2007-992927 | s2cid = 260316768 }}
• Previous exposure to chemotherapy and radiation
• Medications{{sfn|Hoffman|page=172|}}
• Surgical history{{sfn|Hoffman|pages=172–173|}}
• Endocrine disorders{{sfn|Hoffman|page=173|}}{{cite journal | vauthors = Mills JL, Simpson JL, Driscoll SG, Jovanovic-Peterson L, Van Allen M, Aarons JH, Metzger B, Bieber FR, Knopp RH, Holmes LB | title = Incidence of spontaneous abortion among normal women and insulin-dependent diabetic women whose pregnancies were identified within 21 days of conception | journal = The New England Journal of Medicine | volume = 319 | issue = 25 | pages = 1617–23 | date = December 1988 | pmid = 3200277 | doi = 10.1056/NEJM198812223192501 }}{{Update inline|date=September 2017}}
• Genetic abnormalities{{sfn|Hoffman|page=181–182|}}

{{div col end}}

Maintaining a healthy weight and good prenatal care can reduce the risk of miscarriage. Some risk factors can be minimized by avoiding the following:

• Smoking
• Cocaine use
• Alcohol
• Poor nutrition
• Occupational exposure to agents that can cause miscarriage{{sfn|Hoffman|page=272}}
• Medications associated with miscarriage{{sfn|Hoffman|page=72}}
• Substance use

Women who miscarry early in their pregnancy usually do not require any subsequent medical treatment, but they can benefit from support and counseling.{{cite journal | vauthors = Jeve YB, Davies W | title = Evidence-based management of recurrent miscarriages | journal = Journal of Human Reproductive Sciences | volume = 7 | issue = 3 | pages = 159–69 | date = July 2014 | pmid = 25395740 | pmc = 4229790 | doi = 10.4103/0974-1208.142475 | doi-access = free }} Most early miscarriages will be completed on their own; in other cases, medication treatment or aspiration of the products of conception can be used to remove the remaining tissue.{{cite web |url=http://www.babycentre.co.uk/a1039515/understanding-early-miscarriage#ixzz2x52G1IYu |title=Understanding early miscarriage |date=January 2017 |access-date=June 4, 2017 |publisher=BabyCenter, L.L.C. |url-status=live |archive-url=https://web.archive.org/web/20170905095051/https://www.babycentre.co.uk/a1039515/understanding-early-miscarriage#ixzz2x52G1IYu |archive-date=September 5, 2017 |df=mdy-all }} While bed rest has been advocated to prevent miscarriage, this is not of benefit.{{cite journal | vauthors = McCall CA, Grimes DA, Lyerly AD | title = "Therapeutic" bed rest in pregnancy: unethical and unsupported by data | journal = Obstetrics and Gynecology | volume = 121 | issue = 6 | pages = 1305–8 | date = June 2013 | pmid = 23812466 | doi = 10.1097/AOG.0b013e318293f12f }}{{sfn|Hoffman|page = 176}} Those who are experiencing or who have experienced a miscarriage benefit from the use of careful medical language. Significant distress can often be managed by the ability of the clinician to clearly explain terms without suggesting that the woman or couple is somehow to blame.{{cite book|title=Recurrent pregnancy loss|last=Christiansen|first=Ole|publisher=John Wiley & Sons|year=2014|isbn=978-0470672945|location=Chichester, West Sussex, UK|pages=98–99|quote=It is important to bear in mind that some clinical terms can cause great distress and even anger. It is not acceptable to use the term "abortion" for miscarriage, despite its historical clinical prevalence. To the layperson, "abortion" means the elective termination of pregnancy, and while they may have no theoretical objections to that procedure, they are likely to be distressed and even angered at its use in their situation. "Miscarriage" (qualified by adjectives such as recurrent, delayed, early, late, etc.) is easily understood and well accepted.}}

Evidence to support Rho(D) immune globulin after a spontaneous miscarriage is unclear.{{cite journal | vauthors = Karanth L, Jaafar SH, Kanagasabai S, Nair NS, Barua A | title = Anti-D administration after spontaneous miscarriage for preventing Rhesus alloimmunisation | journal = The Cochrane Database of Systematic Reviews | volume = 3 | issue = 3 | pages = CD009617 | date = March 2013 | pmid = 23543581 | doi = 10.1002/14651858.CD009617.pub2 | pmc = 11365588 }} In the UK, Rho(D) immune globulin is recommended in Rh-negative women after 12 weeks gestational age and before 12 weeks gestational age in those who need surgery or medication to complete the miscarriage.{{cite web|author1=Royal College of Obstetric and Gynecologists|title=The Use of Anti-D Immunoglobulin for Rhesus D Prophylaxis|url=https://www.rcog.org.uk/globalassets/documents/guidelines/gtg22antidjuly2013.pdf|access-date=25 September 2014|page=5|date=March 2011|url-status=dead|archive-url=https://web.archive.org/web/20141128192127/https://www.rcog.org.uk/globalassets/documents/guidelines/gtg22antidjuly2013.pdf|archive-date=November 28, 2014|df=mdy-all}}

No treatment is necessary for a diagnosis of complete miscarriage (so long as ectopic pregnancy is ruled out). In cases of an incomplete miscarriage, empty sac, or missed abortion, there are three treatment options: watchful waiting, medical management, and surgical treatment. With no treatment (watchful waiting), most miscarriages (65–80%) will pass naturally within two to six weeks.{{cite journal | vauthors = Kripke C | title = Expectant management vs. surgical treatment for miscarriage | journal = American Family Physician | volume = 74 | issue = 7 | pages = 1125–6 | date = October 2006 | pmid = 17039747 | url = http://www.aafp.org/afp/2006/1001/p1125.html | url-status = live | archive-url = https://web.archive.org/web/20140525195924/http://www.aafp.org/afp/2006/1001/p1125.html | df = mdy-all | archive-date = May 25, 2014 }} This treatment avoids the possible side effects and complications of medications and surgery,{{cite journal | vauthors = Tang OS, Ho PC | title = The use of misoprostol for early pregnancy failure | journal = Current Opinion in Obstetrics & Gynecology | volume = 18 | issue = 6 | pages = 581–6 | date = December 2006 | pmid = 17099326 | doi = 10.1097/GCO.0b013e32800feedb | s2cid = 23354454 }} but increases the risk of mild bleeding, the need for unplanned surgical treatment, and incomplete miscarriage. Medical treatment usually consists of using misoprostol (a prostaglandin) alone or in combination with mifepristone pre-treatment.{{cite journal | vauthors = Schreiber CA, Creinin MD, Atrio J, Sonalkar S, Ratcliffe SJ, Barnhart KT | title = Mifepristone Pretreatment for the Medical Management of Early Pregnancy Loss | journal = The New England Journal of Medicine | volume = 378 | issue = 23 | pages = 2161–2170 | date = June 2018 | pmid = 29874535 | pmc = 6437668 | doi = 10.1056/NEJMoa1715726 }} These medications help the uterus to contract and expel the remaining tissue out of the body. This works within a few days in 95% of cases. Vacuum aspiration or sharp curettage can be used, with vacuum aspiration being lower-risk and more common.

In delayed or incomplete miscarriage, treatment depends on the amount of tissue remaining in the uterus. Treatment can include surgical removal of the tissue with vacuum aspiration or misoprostol.{{cite book|url=https://www.ncbi.nlm.nih.gov/books/NBK333519/|title=Surgery for Family Planning, Abortion, and Postabortion Care|last1=Babigumira|first1=Joseph B.|last2=Vlassoff|first2=Michael|last3=Ahimbisibwe|first3=Asa|last4=Stergachis|first4=Andy |date=2015|publisher=The International Bank for Reconstruction and Development / The World Bank|isbn=978-1464803468|editor-last=Debas|editor-first=Haile T. |location=Washington (DC)|doi=10.1596/978-1-4648-0346-8_ch7|pmid=26741012|editor-last2=Donkor|editor-first2=Peter|editor-last3=Gawande|editor-first3=Atul|editor-last4=Jamison|editor-first4=Dean T.|editor-last5=Kruk|editor-first5=Margaret E.|editor-last6=Mock|editor-first6=Charles N. |archive-url=https://web.archive.org/web/20170910181311/https://www.ncbi.nlm.nih.gov/books/NBK333519/ |archive-date=September 10, 2017|df=mdy-all|url-status=live}} Studies looking at the methods of anaesthesia for surgical management of incomplete miscarriage have not shown that any adaptation from normal practice is beneficial.{{cite journal | vauthors = Calvache JA, Delgado-Noguera MF, Lesaffre E, Stolker RJ | title = Anaesthesia for evacuation of incomplete miscarriage | journal = The Cochrane Database of Systematic Reviews | issue = 4 | pages = CD008681 | date = April 2012 | pmid = 22513963 | doi = 10.1002/14651858.CD008681.pub2 | pmc = 11305452 }}

{{Further|Self-induced abortion}}

An induced abortion may be performed by a qualified healthcare provider for women who cannot continue the pregnancy.{{cite journal|last1=Borgatta|first1=L|date=December 2014|title=Labor Induction Termination of Pregnancy|url=http://www.glowm.com/section_view/heading/Labor%20Induction%20Termination%20of%20Pregnancy/item/443|journal=Global Library of Women's Medicine|volume=GLOWM.10444|doi=10.3843/GLOWM.10444|archive-url=https://web.archive.org/web/20150924082507/http://www.glowm.com/section_view/heading/Labor%20Induction%20Termination%20of%20Pregnancy/item/443|archive-date=September 24, 2015|access-date=25 September 2015|url-status=live|df=mdy-all}} Self-induced abortion performed by a woman or non-medical personnel can be dangerous and is still a cause of maternal mortality in some countries. In some locales, it is illegal or carries heavy social stigma.{{cite journal | vauthors = Haddad LB, Nour NM | title = Unsafe abortion: unnecessary maternal mortality | journal = Reviews in Obstetrics & Gynecology | volume = 2 | issue = 2 | pages = 122–6 | date = 2009 | pmid = 19609407 | pmc = 2709326 }}

Some organisations recommend delaying sex after a miscarriage until the bleeding has stopped to decrease the risk of infection. However, there is not sufficient evidence for the routine use of antibiotics to try to avoid infection in incomplete abortion.{{cite journal | vauthors = May W, Gülmezoglu AM, Ba-Thike K | title = Antibiotics for incomplete abortion | journal = The Cochrane Database of Systematic Reviews | issue = 4 | pages = CD001779 | date = October 2007 | pmid = 17943756 | doi = 10.1002/14651858.CD001779.pub2 | pmc = 12013248 }} Others recommend delaying attempts at pregnancy until one period has occurred to make it easier to determine the dates of a subsequent pregnancy. There is no evidence that getting pregnant in that first cycle affects outcomes, and an early subsequent pregnancy may improve outcomes.{{cite web |title=Trying to conceive soon after a pregnancy loss may increase chances of live birth |url=https://www.nih.gov/news-events/news-releases/trying-conceive-soon-after-pregnancy-loss-may-increase-chances-live-birth |website=National Institutes of Health (NIH) |access-date=1 September 2019 |language=EN |date=12 January 2016}}

Organisations exist that provide information and counselling to help those who have had a miscarriage. Family and friends often conduct a memorial or burial service. Hospitals can provide support and help memorialise the event. Depending on the locale, others desire to have a private ceremony. Providing appropriate support with frequent discussions and sympathetic counselling is part of the evaluation and treatment. Those who experience unexplained miscarriages can be treated with emotional support.

Miscarriage leave is a leave of absence concerning miscarriage. The following countries offer paid or unpaid leave to women who have had a miscarriage.

• The Philippines – 60 days' fully paid leave for miscarriages (before 20 weeks of gestation) or emergency termination of the pregnancy (on the 20th week or after){{cite web |title=REPUBLIC ACT No. 11210 |url=https://lawphil.net/statutes/repacts/ra2019/ra_11210_2019.html |access-date=2021-03-25 |website=lawphil.net}} The husband of the mother gets seven days' fully paid leave up to the 4th pregnancy.{{cite web|url=https://www.ilo.org/dyn/travail/docs/1206/Republic%25252520Act%25252520No%252525208187%25252520-%25252520Paternity%25252520Leave%25252520Act%25252520of%252525201996.pdf|title=Republic Act 8187|access-date=2021-03-25}}
• India – six weeks' leave{{cite web|url=https://labour.gov.in/sites/default/files/TheMaternityBenefitAct1961.pdf|title=Maternity Benefit Act of 1961|access-date=2021-03-25}}
• New Zealand – three days' bereavement leave for both parents{{cite news|url=https://www.bbc.co.uk/news/world-asia-56521171|title=New Zealand to allow bereavement leave|work=BBC News|date=March 25, 2021|access-date=2021-03-25}}
• Mauritius – two weeks' leave{{cite web|url=https://www.ilo.org/wcmsp5/groups/public/---dgreports/---dcomm/---publ/documents/publication/wcms_242615.pdf|title=Maternity and paternity at work|access-date=2021-03-26}}
• Indonesia – six weeks' leave
• Taiwan – five days, one week, or four weeks, depending on how advanced the pregnancy was{{cite web |date=May 12, 2022 |title=Maternity & Paternity Leave in Taiwan |url=https://ins-globalconsulting.com/taiwan-business-guides/learn-about-taiwan-labor-law/taiwan-guide-maternity-paternity-leave/ |website=INS Global}}

File:Karlsruhe Hauptfriedhof Kleinstkinder.jpg

{{See also|Miscarriage and grief|Miscarriage and mental illness}}

Every woman's personal experience of miscarriage is different, and women who have more than one miscarriage may react differently to each event.{{cite journal|last=Reagan|first=Leslie J |date=2003|title=From Hazard to Blessing to Tragedy: Representations of Miscarriage in Twentieth-Century America|journal=Feminist Studies|volume=29|issue=2|pages=357–378|jstor=3178514}}

In Western cultures since the 1980s, medical providers assume that experiencing a miscarriage "is a major loss for all pregnant women". A miscarriage can result in anxiety, depression, or stress for those involved.{{cite journal | vauthors = Hunter A, Tussis L, MacBeth A | title = The presence of anxiety, depression and stress in women and their partners during pregnancies following perinatal loss: A meta-analysis | journal = Journal of Affective Disorders | volume = 223 | pages = 153–164 | date = December 2017 | pmid = 28755623 | doi = 10.1016/j.jad.2017.07.004 | url = https://www.pure.ed.ac.uk/ws/files/42156012/JADacceptedManuscript.pdf | hdl = 20.500.11820/a0bba43c-6418-44dd-bc6c-ed94706ec617 | s2cid = 4919845 | hdl-access = free }}{{cite journal| vauthors = Vismara L |title=Perspectives on perinatal stressful and traumatic experiences (review)|journal=European Journal of Trauma & Dissociation|volume=1|issue=2|pages=111–120|doi=10.1016/j.ejtd.2017.03.006|year=2017}} It can affect the whole family.{{cite journal | vauthors = Garrido-Gimenez C, Alijotas-Reig J | title = Recurrent miscarriage: causes, evaluation and management | journal = Postgraduate Medical Journal | volume = 91 | issue = 1073 | pages = 151–62 | date = March 2015 | pmid = 25681385 | doi = 10.1136/postgradmedj-2014-132672 | s2cid = 207022511 | url = http://pmj.bmj.com/content/91/1073/151 | url-status = live | archive-url = https://web.archive.org/web/20170910181311/http://pmj.bmj.com/content/91/1073/151 | df = mdy-all | archive-date = September 10, 2017 }} Many of those experiencing a miscarriage go through a grieving process.{{cite news|url=http://www.postpartumprogress.com/13-things-you-should-know-about-grief-after-miscarriage-or-baby-loss|title=13 Things To Know About Grief After Miscarriage or Loss|date=2013-05-16|work=Postpartum Progress|access-date=2017-09-09|language=en|url-status=live|archive-url=https://web.archive.org/web/20170909192535/http://www.postpartumprogress.com/13-things-you-should-know-about-grief-after-miscarriage-or-baby-loss|archive-date=September 9, 2017|df=mdy-all}}{{cite web|url=http://www.miscarriagesupport.org.nz/grief-issues-special-to-miscarriage/|title=Grief Issues Special to Miscarriage – the broken bond|website=www.miscarriagesupport.org.nz|date=April 22, 2015|language=en|access-date=2017-09-09|url-status=live|archive-url=https://web.archive.org/web/20170704235250/http://www.miscarriagesupport.org.nz/grief-issues-special-to-miscarriage/|archive-date=July 4, 2017|df=mdy-all}} "Prenatal attachment" often exists that can be seen as parental sensitivity, love and preoccupation directed towards the unborn child.{{cite journal | vauthors = Christiansen DM | title = Posttraumatic stress disorder in parents following infant death: A systematic review | journal = Clinical Psychology Review | volume = 51 | pages = 60–74 | date = February 2017 | pmid = 27838460 | doi = 10.1016/j.cpr.2016.10.007 }} Serious emotional impact is usually experienced immediately after the miscarriage. Some may go through the same loss when an ectopic pregnancy is terminated.{{cite web |url=https://www.nhs.uk/conditions/ectopic-pregnancy/ |title=Ectopic pregnancy |author= |date=August 23, 2022 |website=NHS |url-status=live |archive-url=https://web.archive.org/web/20230725085050/https://www.nhs.uk/conditions/ectopic-pregnancy/ |archive-date=July 25, 2023}} In some, the realisation of the loss can take weeks. Providing family support to those experiencing the loss can be challenging because some find comfort in talking about the miscarriage, while others may find the event painful to discuss. The father can have the same sense of loss. Expressing feelings of grief and loss can sometimes be harder for men. Some women can begin planning their next pregnancy after a few weeks of having a miscarriage. For others, planning another pregnancy can be difficult.{{cite web | url = https://www.miscarriageassociation.org.uk/wp-content/uploads/2016/10/Thinking-about-another-pregnancy.pdf | title = Thinking About Another Pregnancy | publisher = Miscarriage Association | access-date = 4 September 2017 | date = 2013 | url-status = live | archive-url = https://web.archive.org/web/20170905051002/https://www.miscarriageassociation.org.uk/wp-content/uploads/2016/10/Thinking-about-another-pregnancy.pdf | archive-date = September 5, 2017 | df = mdy-all }} Some facilities acknowledge the loss. Parents can name and hold their infant. They may be given mementos such as photos and footprints. Some conduct a funeral or memorial service. They may express the loss by planting a tree.{{cite book|title=Becoming Parents and Overcoming Obstacles: Understanding the Experience of Miscarriage, Premature Births, Infertility, and Postnatal Depression|last=Emanuela.|first=Quagliata|date=2013|publisher=Karnac Books|isbn=978-1782200185|page=63|oclc=858653965}}

Some health organizations recommend that sexual activity be delayed after a miscarriage. The menstrual cycle should resume after about three to four months.{{cite web |url=https://www.nhs.uk/conditions/miscarriage/afterwards/ |title=Miscarriage – Afterwards |author= |website=NHS |date=May 10, 2023 |url-status=live |archive-url=https://web.archive.org/web/20230510204654/https://www.nhs.uk/conditions/miscarriage/afterwards/ |archive-date=May 10, 2023 |df=mdy-all}} Women reported that they were dissatisfied with the care they received from physicians and nurses.{{cite journal|last=Robinson|first=Joanne|date=2014-03-01|title=Provision of information and support to women who have suffered an early miscarriage (review)|journal=British Journal of Midwifery|volume=22|issue=3|pages=175–180|doi=10.12968/bjom.2014.22.3.175|issn=0969-4900}}{{Context inline|date=May 2022}}

Some parents want to try to have a baby very soon after the miscarriage. The decision to try to become pregnant again can be difficult. Reasons exist that may prompt parents to consider another pregnancy. For older mothers, there may be some sense of urgency. Other parents are optimistic that future pregnancies are likely to be successful. Many are hesitant and want to know about the risk of having another or more miscarriages. Some clinicians recommend that the women have one menstrual cycle before attempting another pregnancy. This is because the date of conception may be hard to determine. Also, the first menstrual cycle after a miscarriage can be much longer or shorter than expected. Parents may be advised to wait even longer if they have experienced late miscarriage or molar pregnancy, or are undergoing tests. Some parents wait for six months based on recommendations from their healthcare provider.

Research shows that depression after a miscarriage or stillbirth can continue for years, even after the birth of a subsequent child. Medical professionals are advised to take previous loss of a pregnancy into account when assessing risks for postnatal depression following the birth of a subsequent infant. It is believed that supportive interventions may improve the health outcomes of both the mother and the child.{{cite web |title=Women Who Miscarry Have Long-lasting Mental Health Problems |url=https://www.urmc.rochester.edu/news/story/women-who-miscarry-have-long-lasting-mental-health-problems |website=University of Rochester Medical Center |access-date=April 11, 2023}}

The risks of having another miscarriage vary according to the cause. The risk of having another miscarriage after a molar pregnancy is very low. The risk of another miscarriage is highest after the third miscarriage. Pre-conception care is available in some locales.

There is a significant association between miscarriage and later development of coronary artery disease, but not cerebrovascular disease.{{cite journal | vauthors = Oliver-Williams CT, Heydon EE, Smith GC, Wood AM | title = Miscarriage and future maternal cardiovascular disease: a systematic review and meta-analysis | journal = Heart | volume = 99 | issue = 22 | pages = 1636–44 | date = November 2013 | pmid = 23539554 | pmc = 3812894 | doi = 10.1136/heartjnl-2012-303237 }}{{sfn|Hoffman|page = 172}}

Around 15% of known pregnancies end in miscarriage, totaling around 23 million miscarriages per year worldwide.{{cite journal |vauthors=Quenby S, Gallos ID, Dhillon-Smith RK, Podesek M, et al |title=Miscarriage matters: the epidemiological, physical, psychological, and economic costs of early pregnancy loss |journal=Lancet |volume=397 |issue=10285 |pages=1658–1667 |date=May 2021 |pmid=33915094 |doi=10.1016/S0140-6736(21)00682-6 |url=}} Miscarriage rates among all fertilized zygotes are around 30% to 50%. A 2012 review found the risk of miscarriage between 5 and 20 weeks from 11% to 22%. Up to the 13th week of pregnancy, the risk of miscarriage each week was around 2%, dropping to 1% in week 14 and reducing slowly between 14 and 20 weeks.

The precise rate is not known because a large number of miscarriages occur before pregnancies become established and before the woman is aware she is pregnant.{{cite journal | vauthors = Ammon Avalos L, Galindo C, Li DK | title = A systematic review to calculate background miscarriage rates using life table analysis | journal = Birth Defects Research. Part A, Clinical and Molecular Teratology | volume = 94 | issue = 6 | pages = 417–23 | date = June 2012 | pmid = 22511535 | doi = 10.1002/bdra.23014 }} Additionally, those with bleeding in early pregnancy may seek medical care more often than those not experiencing bleeding. Although some studies attempt to account for this by recruiting women who are planning pregnancies and testing for very early pregnancy, they still are not representative of the wider population.

In 2010, 50,000 inpatient admissions for miscarriage occurred in the UK.

Society's reactions to miscarriage have changed over time. In the early 20th century, the focus was on the mother's physical health and the difficulties and disabilities that miscarriage could produce. Other reactions, such as the expense of medical treatments and relief at ending an unwanted pregnancy, were also heard. In the 1940s and 1950s, people were more likely to express relief, not because the miscarriage ended an unwanted or mistimed pregnancy, but because people believed that miscarriages were primarily caused by birth defects, and miscarrying meant that the family would not raise a child with disabilities. The dominant attitude in the mid-century was that a miscarriage, although temporarily distressing, was a blessing in disguise for the family and that another pregnancy and a healthier baby would soon follow, especially if women trusted physicians and reduced their anxieties. Media articles were illustrated with pictures of babies, and magazine articles about miscarriage ended by introducing the healthy baby—usually a boy—that shortly followed it.

Beginning in the 1980s, miscarriage in the US was primarily framed in terms of the individual woman's emotional reaction, especially her grief over a tragic outcome. The subject was portrayed in the media with images of an empty crib or an isolated, grieving woman, and stories about miscarriage were published in general-interest media outlets, not just women's magazines or health magazines. Family members were encouraged to grieve, to memorialize their losses through funerals and other rituals, and to think of themselves as being parents. This shift to recognizing these emotional responses was partly due to medical and political successes, which created an expectation that pregnancies are typically planned and safe, and to women's demands that their emotional reactions no longer be dismissed by the medical establishments. It also reinforces the anti-abortion movement's belief that human life begins at conception or early in pregnancy, and that motherhood is a desirable life goal. The modern one-size-fits-all model of grief does not fit every woman's experience, and an expectation to perform grief creates unnecessary burdens for some women. The reframing of miscarriage as a private emotional experience brought less awareness of miscarriage and a sense of silence around the subject, especially compared to the public discussion of miscarriage during campaigns for access to birth control during the early 20th century, or the public campaigns to prevent miscarriages, stillbirths, and infant deaths by reducing industrial pollution during the 1970s.{{cite news|url=https://www.thecut.com/2018/04/the-history-of-talking-about-miscarriage.html|title=The History of Talking About Miscarriage|last=Blei|first=Daniela |work=The Cut|access-date=2018-04-26}}

In places where induced abortion is illegal or carries a social stigma, suspicion may surround miscarriage, complicating an already sensitive issue.

Developments in ultrasound technology (in the early 1980s) allowed them to identify earlier miscarriages.

Miscarriages may be tracked for purposes of health statistics, but they are not usually recorded individually. For example, under UK law, all stillbirths should be registered,{{cite web |title=Register a stillbirth – GOV.UK |url=https://www.gov.uk/register-stillbirth |url-status=live |archive-url=https://web.archive.org/web/20170905051919/https://www.gov.uk/register-stillbirth |archive-date=September 5, 2017 |access-date=September 5, 2017 |website=www.gov.uk |df=mdy-all}} although this does not apply to miscarriages. According to French statutes, an infant born before the age of viability, determined to be 28 weeks, is not registered as a 'child'. If birth occurs after this, the infant is granted a certificate that allows the parents to have a symbolic record of that child. This certificate can include a registered and given name to allow a funeral and acknowledgement of the event.Communiqué de presse de Rachida Dati, Garde des Sceaux, ministre de la Justice et de Roselyne Bachelot-Narquin, ministre de la Santé, de la Jeunesse, des Sports et de la Vie associative, « Possibilité de demande d'un acte d'enfant sans vie », 22 août 2008, [http://www.sante.gouv.fr/possibilite-de-demande-d-un-acte-d-enfant-sans-vie.html lire en ligne] {{Webarchive|url=https://web.archive.org/web/20120419184246/http://www.sante.gouv.fr/possibilite-de-demande-d-un-acte-d-enfant-sans-vie.html |date=April 19, 2012 }}{{cite web|url=https://www.service-public.fr/|title=Accueil Particuliers {{!}} service-public.fr|website=www.service-public.fr|language=fr|access-date=2017-11-04}}{{Citation|title=Décret n°74-449 du 15 mai 1974 relatif au livret de famille et à l'information des futurs époux sur le droit de la famille – Article 9|date=15 May 1974|url=https://www.legifrance.gouv.fr/affichTexteArticle.do?idArticle=LEGIARTI000006285245&cidTexte=JORFTEXT000000328986|access-date=2017-11-04}}

Spontaneous abortion is known from multiple species of non-hominid placental mammal and other vertebrates with convergent embryonic development, such as elasmobranch fishes. There are a variety of known risk factors; for example, in sheep, miscarriage may be caused by crowding through doors or being chased by dogs.Spencer, James. [https://books.google.com/books?id=RXMuAAAAYAAJ&pg=PA124 Sheep Husbandry in Canada] {{webarchive|url=https://web.archive.org/web/20150924203629/https://books.google.com/books?id=RXMuAAAAYAAJ&pg=PA124&lpg=PA124&dq=abortion+and+husbandry&ct=result |date=September 24, 2015 }}, page 124 (1911). In cows, spontaneous abortion may be caused by contagious diseases, such as brucellosis or Campylobacter, but often can be controlled by vaccination.[http://www.teara.govt.nz/1966/B/BeefCattleAndBeefProduction/ManagementAndHusbandryOfBeefCattle/en "Beef cattle and Beef production: Management and Husbandry of Beef Cattle"] {{webarchive|url=https://web.archive.org/web/20090101142401/http://www.teara.govt.nz/1966/B/BeefCattleAndBeefProduction/ManagementAndHusbandryOfBeefCattle/en |date=January 1, 2009 }}, Encyclopaedia of New Zealand (1966). In many species of sharks and rays, stress-induced miscarriage occurs frequently on capture.{{cite journal|vauthors=Adams KR, Fetterplace LC, Davis AR, Taylor MD, Knott NA|title=Sharks, rays and abortion: The prevalence of capture-induced parturition in elasmobranchs|journal=Biological Conservation|date=January 2018|volume=217|pages=11–27|doi=10.1016/j.biocon.2017.10.010|bibcode=2018BCons.217...11A |s2cid=90834034 |url=http://marxiv.org/k2qvy/|access-date=July 12, 2019|archive-date=February 23, 2019|archive-url=https://web.archive.org/web/20190223020619/https://marxiv.org/k2qvy/|url-status=dead}}

Other diseases and risks are also known to make animals susceptible to miscarriage. Spontaneous abortion occurs in pregnant prairie voles when their mate is removed and they are exposed to a new male,{{cite journal | vauthors = Fraser-Smith AC | title = Male-induced pregnancy termination in the prairie vole, Microtus ochrogaster | journal = Science | volume = 187 | issue = 4182 | pages = 1211–3 | date = March 1975 | pmid = 1114340 | doi = 10.1126/science.1114340 | bibcode = 1975Sci...187.1211S }} an example of the Bruce effect, although this effect is seen less in wild populations than in the laboratory.{{cite journal |doi=10.1007/s00265-002-0484-0 |title=A field test of the Bruce effect in the monogamous prairie vole (Microtus ochrogaster) |year=2002 |last1=Mahady |first1=Scott |last2=Wolff |first2=Jerry |journal=Behavioral Ecology and Sociobiology |volume=52 |issue=1 |pages=31–7 |jstor=4602102|s2cid=10952123 }} Female mice who had spontaneous abortions showed a sharp rise in the amount of time spent with unfamiliar males preceding the abortion than those who did not.{{cite journal | vauthors = Becker SD, Hurst JL | title = Female behaviour plays a critical role in controlling murine pregnancy block | journal = Proceedings. Biological Sciences | volume = 276 | issue = 1662 | pages = 1723–9 | date = May 2009 | pmid = 19324836 | pmc = 2660991 | doi = 10.1098/rspb.2008.1780 | jstor = 30245000 }}

• Pregnancy and Infant Loss Remembrance Day
• Perinatal bereavement
• Reproductive loss
• Embryo resorption
• Fetal resorption

{{reflist|refs=

{{cite book |title=The Johns Hopkins Manual of Gynecology and Obstetrics |url=https://books.google.com/books?id=4Sg5sXyiBvkC&pg=PA438 |url-status=live |publisher=Lippincott Williams & Wilkins |edition=4 |pages=438–439 |date=2012 |archive-url=https://web.archive.org/web/20170910181311/https://books.google.com/books?id=4Sg5sXyiBvkC&pg=PA438 |archive-date=September 10, 2017 |isbn=978-1451148015 |df=mdy-all}}

{{cite web |date=2013-07-15 |title=How many people are affected by or at risk for pregnancy loss or miscarriage? |url=http://www.nichd.nih.gov/health/topics/pregnancyloss/conditioninfo/Pages/risk.aspx |url-status=live |archive-url=https://web.archive.org/web/20150402093633/http://www.nichd.nih.gov/health/topics/pregnancyloss/conditioninfo/Pages/risk.aspx |archive-date=April 2, 2015 |website=www.nichd.nih.gov |df=mdy-all |access-date=14 March 2015}}

{{cite journal |vauthors=Oliver A, Overton C |title=Diagnosis and management of miscarriage |journal=The Practitioner |volume=258 |issue=1771 |pages=25–8, 3 |date=May 2014 |pmid=25055407}}

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• {{cite book | last1 = Hoffman | first1 = Barbara |author2=J. Whitridge Williams | year = 2012 | title = Williams Gynecology |edition=2nd | location = New York | publisher = McGraw-Hill Medical | isbn = 978-0071716727|ref={{harvid|Hoffman}} }}

{{Wikiquote}}

{{Medical resources

| DiseasesDB = 29

| ICD10 = {{ICD10|O|03||O|00}}

| ICD9 = {{ICD9|634}}

| ICDO =

| OMIM =

| MedlinePlus = 001488

| eMedicineSubj = search

| eMedicineTopic = miscarriage

| MeshID = D000022

| Scholia = Q28693

}}

{{Women's health|state=collapsed}}

{{Pathology of pregnancy, childbirth and the puerperium | state=collapsed}}

{{Chromosomal abnormalities | state = collapsed}}

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Category:Pathology of pregnancy, childbirth and the puerperium

Category:Theriogenology

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