superfecundation#Use in mythology

Superfecundation is the fertilization of two or more ova from the same menstrual cycle by sperm from the same or different males, whether through separate acts of intercourse or during a single sexual encounter with multiple males (e.g. double penetration). This can potentially result in twin babies that have different biological fathers.{{cite magazine|url=https://time.com/3851843/twins-complications/ |title=The Science of How Women Can Have Twins With 2 Different Fathers|first=Justin|last=Worland|date=May 8, 2015|magazine=Time|access-date=March 23, 2017}}{{cite web|url=https://sogc.org/publications-resources/public-information-pamphlets.html?id=33|title=Public Education Pamphlets|work=sogc.org}}

The term superfecundation is derived from fecund, meaning able to produce offspring. Homopaternal superfecundation is a form of twinning where fertilization of two separate ova occurs as a result of two or more distinct instances of intercourse or insemination with the same male partner or donor, leading to fraternal twins.{{cite journal |pmid=10641935 |year=2000 |last1=Ambach |first1=E |title=Superfecundation and dual paternity in a twin pregnancy ending with placental abruption |journal=Journal of Forensic Sciences |volume=45 |issue=1 |pages=181–3 |last2=Parson |first2=W |last3=Brezinka |first3=C |doi=10.1520/JFS14656J }} Heteropaternal superfecundation, on the other hand, is an atypical form of twinning that results in twins that are genetically half siblings – sharing the same biological mother, but with different biological fathers.

Conception

Sperm cells can live inside a human female's body for up to five days, and once ovulation occurs, the egg remains viable for 12–48 hours before it begins to disintegrate.{{Cite web|last=Dunkin|first=Mary Anne|title=Sperm: How Long Sperm Live, Sperm Count, and More|url=https://www.webmd.com/infertility-and-reproduction/guide/sperm-and-semen-faq|access-date=2022-01-06|website=WebMD|language=en}} Superfecundation most commonly happens within hours or days of the first instance of fertilization with ova released during the same cycle.

Ovulation is normally suspended during pregnancy to prevent further ova becoming fertilized and to help increase the chances of a full-term pregnancy. However, if an ovum is atypically released after the female was already impregnated when previously ovulating, a chance of a second pregnancy occurs, albeit at a different stage of development. This is known as superfetation.{{cite journal |doi=10.1016/j.ajog.2015.10.930 |pmid=26548710 |title=A review of the mechanisms and evidence for typical and atypical twinning |journal=American Journal of Obstetrics and Gynecology |volume=214 |issue=2 |pages=172–91 |year=2016 |last1=McNamara |first1=Helen C. |last2=Kane |first2=Stefan C. |last3=Craig |first3=Jeffrey M. |last4=Short |first4=Roger V. |last5=Umstad |first5=Mark P. }}

Heteropaternal superfecundation

Heteropaternal superfecundation is common in animals such as cats and dogs. Stray dogs can produce litters in which every puppy has a different sire. Though rare in humans, cases have been documented. In one study on humans, the frequency was 2.4% among dizygotic twins whose parents had been involved in paternity suits.{{cite journal |pmid=1488855 |year=1992 |last1=Wenk |first1=R. E. |title=How frequent is heteropaternal superfecundation? |journal=Acta Geneticae Medicae et Gemellologiae |volume=41 |issue=1 |pages=43–7 |last2=Houtz |first2=T |last3=Brooks |first3=M |last4=Chiafari |first4=F. A. |doi=10.1017/S000156600000249X |s2cid=23507167 |doi-access=free }}

Selected cases involving superfecundation

In 1982, twins who were born with two different skin colors were discovered to be conceived as a result of heteropaternal superfecundation.{{Cite web |url=https://www.scopus.com/record/display.uri?eid=2-s2.0-0020008620&origin=inward&txGid=F6227767DB3CDB724EA92EFC60A5A985.wsnAw8kcdt7IPYLO0V48gA:2 |title=Scopus - Error |access-date=2018-10-13 |archive-date=2020-04-27 |archive-url=https://web.archive.org/web/20200427163635/https://www.scopus.com/error.uri |url-status=dead }}

In 1995, a young woman gave birth to diamniotic monochorionic twins, who were originally assumed to be monozygotic twins until a paternity suit led to a DNA test. This led to the discovery that the twins had different fathers.

In 2001, a case of spontaneous monopaternal superfecundation was reported after a woman undergoing IVF treatments gave birth to quintuplets after only two embryos were implanted. Genetic testing supported that the twinning was not a result of the embryos splitting, and that all five boys shared the same father.{{cite journal |doi=10.1016/S0015-0282(01)01976-8 |pmid=11532493 |title=Monopaternal superfecundation of quintuplets after transfer of two embryos in an in vitro fertilization cycle |journal=Fertility and Sterility |volume=76 |issue=3 |pages=621–3 |year=2001 |last1=Amsalem |first1=Hagai |last2=Tsvieli |first2=Rimona |last3=Zentner |first3=Bat Sheva |last4=Yagel |first4=Simcha |last5=Mitrani-Rosenbaum |first5=Stella |last6=Hurwitz |first6=Arye |doi-access=free }}

In 2008, on the Maury Show a paternity test on live television established a heteropaternal superfecundation.{{Cite web |last=Griffith |first=Ivy |date=2022-03-21 |title=The Maury Show Canceled: A Look Back at the Wildest Moments |url=https://celebmagazine.com/maury-show-canceled-look-back-wildest-moments/ |access-date=2023-08-17 |website=CelebMagazine |language=en-US}}

In 2015, a judge in New Jersey ruled that a man should only pay child support for one of two twins, as he was only the biological father to one of the children.{{cite web |url=https://edition.cnn.com/2015/05/08/us/new-jersey-twins-two-fathers |title=New Jersey judge rules twin girls have different fathers |website=CNN |date=8 May 2015 }}

In 2017, an IVF-implanted surrogate mother gave birth to two children: one genetically unrelated child from an implanted embryo, and a biological child from her own egg and her husband's sperm.{{cite web|url=http://www.cnn.com/2017/11/03/health/surrogate-mom-two-babies/index.html|title=Surrogate mom delivers two babies, one her own|publisher=CNN|date=November 3, 2017|author=Susan Scutti}}

In 2019, a Chinese woman was reported to have two babies from different fathers, one of whom was her husband and the other was a man having a secret affair with her during the same time.{{cite web|url=https://www.dailysabah.com/asia/2019/03/29/chinese-woman-gives-birth-to-twin-babies-from-different-fathers-in-one-in-a-million-case|title=Chinese woman gives birth to twin babies from different fathers in one-in-a-million case|website=DailySabah|date=29 March 2019 }}

In 2022, a 19-year-old Brazilian from Mineiros gave birth to twins from two different fathers with whom she had sex on the same day.{{cite web |url=https://www.sciencetimes.com/articles/39869/20220912/19-year-old-brazilian-woman-gives-birth-to-twins-from-2-different-fathers.htm |title=19-Year-Old Brazilian Woman Gives Birth to Twins From 2 Different Fathers |website=Science Times |date=12 September 2022 }}

Mythology

Greek mythology holds many cases of superfecundation:

Leda lies with both her husband Tyndareus and with the god Zeus, the latter in the guise of a swan. Nine months later, she bears two daughters: Clytemnestra by Tyndareus and Helen by Zeus. This happens again; this time Leda bears two sons: Castor by Tyndareus and Pollux by Zeus.
Alcmene lies with Zeus, who is disguised as her husband Amphitryon; Alcmene later lies with the real Amphitryon and gives birth to two sons: Iphicles by Amphitryon and Heracles by Zeus.
Chione lies with both Apollo and Hermes on the same night, and falls pregnant. She bears two sons; Autolycus for Hermes and Philammon for Apollo.

superfecundation#Use in mythology

Conception

Heteropaternal superfecundation

Selected cases involving superfecundation

Mythology

See also

References

Further reading