font size

Definition of Superfetation

Superfetation: An extremely rare situation in which a pregnant woman becomes pregnant a second time with another (younger) fetus. Superfetation is characterized by the fertilization and the implantation of a second oocyte in a uterus already containing the product of a previous conception. Superfetation is different from the process of twinning or multiple gestation and involves the conception of an additional fetus during an established pregnancy. With superfetation, the two fetuses have different gestational ages and due dates. Superfetation can occur in some animals but is so rare in humans that fewer than 10 cases have been reported in the medical literature.

Source: MedTerms™ Medical Dictionary
http://www.medterms.com/script/main/art.asp?articlekey=105927
Last Editorial Review: 6/14/2012

Drug Medical Dictionary of Terms by Letter

Top RxList Drug News

Parenting and Pregnancy

Get tips for baby and you.

advertisement
advertisement
Use Pill Finder Find it Now See Interactions

Pill Identifier on RxList

  • quick, easy,
    pill identification

Find a Local Pharmacy

  • including 24 hour, pharmacies

Interaction Checker

  • Check potential drug interactions
Search the Medical Dictionary for Health Definitions & Medical Abbreviations