Congenital and Fetal Effects After Mifepristone Exposure and Continuation of Pregnancy: A Systematic Review.

Mifepristone is an anti-progestational drug that is the first component of the standard medical abortion regimen. For women who take mifepristone and then do not take misoprostol, which is the second component of the medical abortion regimen, it is possible that their pregnancy may continue to live birth. Since mifepristone is commonly used for medical abortion up to 9-10 weeks gestation, any adverse or teratogenic effects on the developing embryo/fetus must be considered, given exposure during the critical time of its development and organogenesis. Toxicology and teratology reports have cited studies demonstrating teratogenic effect of mifepristone in some animals. Current clinical guidelines for women exposed to mifepristone in the first trimester of pregnancy state that it is not known to be teratogenic based on limited published evidence from humans. The aim of this narrative systematic review was to investigate embryonic/fetal exposure to mifepristone and any association with congenital or fetal anomalies. This study was conducted by systematic searches of health databases from inception to February 2024. The references of relevant citations were manually searched to retrieve any additional citations not captured in database searching. Congenital anomalies and adverse outcomes were encountered at various doses of mifepristone exposure. A number of the congenital anomalies encountered in this review were explained by circumstances other than exposure to mifepristone. The present systematic review did not find data to support mifepristone being implicated as a teratogen.

Progesterone after mifepristone: A pilot prospective single arm clinical trial for women who have changed their mind after commencing medical abortion.

AIM: This pilot study aimed to assess the utility of an oral progesterone treatment protocol for women who commenced medical abortion and then changed their mind and wished instead to maintain their pregnancy. METHODS: The Progesterone-After-Mifepristone-pilot for efficacy and reproducibility (PAMper) trial was designed as a prospective single-arm pilot clinical trial, conducted via telehealth. Women aged 18 to 45 years in Australia who reported ingesting mifepristone within the last 72 h to initiate medical abortion and had not taken misoprostol were included. Initial contact was by a web-based form. Following informed consent, participants were prescribed oral progesterone to be taken 400 mg twice per day for 3 days then 400 mg at night until completion of a 19 day course. Pregnancy viability was assessed by ultrasound scan after 14 days of progesterone treatment. RESULTS: Between October 2020 and June 2021, nine women contacted the PAMper trial, of whom six enrolled and commenced progesterone treatment. These women reported ingesting mifepristone at 40-70 days of gestation, with progesterone being commenced within 5.7-72 h of mifepristone ingestion. Five participants had ongoing, live pregnancies at the primary endpoint (ultrasound at >2 weeks). One participant had a miscarriage after 9 days of progesterone treatment. There were no clinically significant adverse events. CONCLUSION: This small study demonstrated a clinically sound protocol for researching the use of progesterone-after-mifepristone for women in this circumstance. Results of this pilot study support the need for further larger scale trials in this field.

Progesterone for preventing pregnancy termination after initiation of medical abortion with mifepristone.

INTRODUCTION: Abortion is often a difficult and traumatic decision for a woman to make. Perhaps greater distress occurs when a woman commences a medical abortion but then changes her mind and wishes to keep the now-threatened pregnancy. One published case series detailed a potential method to counter/reverse the abortifacient effect of mifepristone by administering parenteral progesterone in such situations. OBJECTIVES: The present report details cases of women in similar circumstances who have been treated with progesterone. The aims were to document occurrences of where women have changed their mind after commencing medical abortion, as well as to explore some of the controversies and clinical issues surrounding their circumstances. METHODS: Women who had commenced medical abortion by ingesting mifepristone but who had not taken misoprostol independently contacted a national pregnancy support service the same day. Those meeting criteria for treatment received progesterone pessaries per vaginum for two weeks. RESULTS: Cases: 28-year-old woman, 6 weeks plus 1 day gestation; 35-year-old woman, 8 weeks plus 5 days gestation; and 27-year-old woman, 7 weeks plus 3 days gestation. Outcomes respectively were: healthy male baby delivered at 39 weeks gestation; healthy male baby delivered at term; and completed medical abortion. CONCLUSIONS: Women have changed their mind after commencing medical abortion. Progesterone use in early pregnancy is low risk and its application to counter the effects of mifepristone in such circumstances may be clinically beneficial in preserving her threatened pregnancy. Further research is required, however, to provide definitive evidence.