Do mifepristone or misporostol cause fetal malformations?

There is no known risk of fetal malformations after the use of mifepristone.

The use of misoprostol in the first 12 weeks of pregnancy is associated with a small increased risk of fetal malformations. The risk is very low, less than 10 per 1,000 ongoing pregnancies. Most of these malformations cannot be detected by ultrasound.

After 12 weeks, there is no increased risk at all.

Sources

1. Turner, Joseph V., Deborah Garratt, Anna Barwick, Lucas A. McLindon, M. Joy Spark, and Angela Smith. 2024. ‘Congenital and Fetal Effects After Mifepristone Exposure and Continuation of Pregnancy: A Systematic Review’. Clinical Pharmacology and Therapeutics, November. https://doi.org/10.1002/cpt.3392
2. Philip, Neena, Caitlin S Shannon, and Beverly Winikoff. 2003. ‘Misoprostol and Teratogenicity: Reviewing the Evidence. Report of a Meeting.’ Robert H. Ebert Program on Critical Issues in Reproductive Health Publication Series. New York: Population Council and Gynuity Health Products. https://knowledgecommons.popcouncil.org/cgi/viewcontent.cgi?article=2658&context=departments_sbsr-rh