moro reflex

Ernst Moro elicited the Moro reflex by slapping the pillow on both sides of the infant's head. Other methods have been used since then, including rapidly lowering the infant (while supported) to a sudden stop and pinching the skin of the abdomen. Today, the most common method is the head drop, where the infant is supported in both hands and tilted suddenly so the head is a few centimeters lower than the level of the body.

The Moro reflex may be observed in incomplete form in premature birth after the 25th week of gestation, and is usually present in complete form by week 30 (third trimester). Absence or asymmetry of either abduction or adduction by 2 to 3 months age can be regarded as abnormal, as can persistence of the reflex in infants older than 6 months. Furthermore, absence during the neonatal period may warrant assessment for the possibility of developmental complications such as birth injury or interference with brain formation. Asymmetry of the Moro reflex is especially useful to note, as it is almost always a feature of root, plexus, or nerve disease.{{Cite book|title=Neurology of the newborn|last=Volpe|first=Joseph J.|journal=Major Problems in Clinical Pediatrics|date=2008|volume=22|publisher=Saunders/Elsevier|isbn=9781416039952|pages=1–648|pmid=7022034|oclc=878742566}}

The Moro reflex is impaired or absent in infants with kernicterus.{{Cite web|url=https://rarediseases.org/rare-diseases/kernicterus/|title=Kernicterus|website=NORD (National Organization for Rare Disorders)|access-date=2019-08-06}}

An exaggerated Moro reflex can be seen in infants with severe brain damage that occurred in-utero, including microcephaly and hydranencephaly.{{Cite web|url=https://www.sciencedirect.com/topics/medicine-and-dentistry/moro-reflex|title=Moro Reflex - an overview|last=Multiple authors|website=ScienceDirect Topics|access-date=2019-08-01}} Exaggeration of the Moro reflex, manifesting either as low threshold or excessive clutching, often occurs in newborns with moderate hypoxic-ischemic encephalopathy. The Moro reflex is also exaggerated in infants withdrawing from narcotics.{{Cite journal|last1=Chasnoff|first1=Ira J.|last2=Burns|first2=William J.|date=1984|title=The Moro Reaction: A Scoring System for Neonatal Narcotic Withdrawal|journal=Developmental Medicine & Child Neurology|volume=26|issue=4|pages=484–489|doi=10.1111/j.1469-8749.1984.tb04475.x|pmid=6479468|s2cid=36440317|issn=1469-8749}}

Persistence of the Moro reflex beyond 6 months of age is noted only in infants with severe neurological defects, including cerebral palsy.{{cite book |last1=Samuels |first1=Martin A. |author-link1=Martin A. Samuels |last2=Ropper |first2=Allan H. |title=Adams and Victor's Principles of Neurology |year=2009 |publisher=McGraw-Hill Medical |location=New York |isbn=9780071499927 |chapter-url=http://www.mhprofessional.com/product.php?isbn=007149992X |edition=9th |access-date=7 February 2013 |chapter=Normal Development and Deviations in Development of the Nervous System}}{{Cite journal|last1=Agarwal|first1=Anil|last2=Verma|first2=Indreshwar|date=December 2012|title=Cerebral palsy in children: An overview|journal=Journal of Clinical Orthopaedics and Trauma|volume=3|issue=2|pages=77–81|doi=10.1016/j.jcot.2012.09.001|pmc=3872805|pmid=26403442}}

The Moro reflex was first described in western medicine by Austrian pediatrician Ernst Moro (1874–1951) in 1918. Moro referred to it as the Umklammerungsreflex (embracing reflex). In this publication, he stated: "When a young infant is placed on the examination table and one taps with hands on both sides of the pillow, there follows a rapid symmetrical extending abduction of both extremities, which approach each other in adduction immediately thereafter". According to him, this reflex should disappear after the infant's first 3–6 months of life. Since then, the Moro reflex has been used to detect early neurological problems in infants.{{Cite journal|last1=Weirich|first1=Angela|last2=Hoffmann|first2=Georg F.|s2cid=27343540|date=2005-10-01|title=Ernst Moro (1874–1951)—A great pediatric career started at the rise of university-based pediatric research but was curtailed in the shadows of Nazi laws|journal=European Journal of Pediatrics|volume=164|issue=10|pages=599–606|doi=10.1007/s00431-005-1703-2|pmid=15931526|issn=1432-1076}} Absence or prolonged retention of Moro reflex can be signs that the infants need neurological attention.{{Citation|last1=Edwards|first1=Christopher W.|title=Moro Reflex|date=2019|url=http://www.ncbi.nlm.nih.gov/books/NBK542173/|work=StatPearls|publisher=StatPearls Publishing|pmid=31194330|access-date=2019-08-01|last2=Al Khalili|first2=Yasir}}

The Moro reflex may be a survival instinct to help the infant cling to its mother. If the infant lost its balance, the reflex caused the infant to embrace its mother and regain its hold on the mother’s body.{{cite book |last=Berk |first=Laura E. |title=Child Development |year=2009 |publisher=Pearson |location=Boston |isbn=978-0-205-61559-9 |url=https://archive.org/details/childdevelopment02berk |edition=8th |access-date=7 February 2013 |url-access=registration }} The Moro reflex might also be an alarm signal from the baby who is about to lose support, and the spread arms provide extremities for where to be grabbed by its handler to prevent a fall. {{cite book |last=Altin |first=Simon Peter |author-link= |date=2024 |title=Paleothinking: Going Back in Time to Understand Human Nature |url= |location= |publisher=KDP |page=67 |isbn=979-8875858369}}

{{reflist}}

• [http://medlineplus.gov/ Medline Plus]: [https://www.nlm.nih.gov/medlineplus/ency/article/003293.htm Moro reflex]
• [http://www.neurology.org/cgi/content/full/68/6/437/DC1 Pathologic Moro Reflex in an adult following acute demyelinating lesion of unknown origin in the medulla oblongata (Neurology)]

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