Ulipristal acetate and pregnancy outcome-an observational study

STUDYQUESTION: Is the failure of the selective progesterone receptor modulator ulipristal acetate (UPA) as emergency contraception (EC; 30 mg, single) or inadvertent exposure for myoma treatment (5 mg/d) in pregnancy associated with a higher risk of birth defects, spontaneous abortion (SAB) or elective termination of pregnancy (ETOP)? SUMMARY ANSWER: We did not find an increased risk for birth defects, SABs or ETOPs after UPA exposure during implantation and early embryogenesis. WHAT IS KNOWN ALREADY: Pregnancy outcome data after exposure to UPA are very limited. In cases of EC failure or unplanned pregnancy during myoma treatment, women need well-grounded risk assessment to minimize anxiety and prevent unjustified termination of pregnancy. STUDY DESIGN, SIZE, DURATION: Observational study of prospectively ascertained pregnancies from the German Embryotox institute with UPA exposure (EC, n = 95; myoma, n = 7). Four retrospectively reported pregnancy outcomes were evaluated separately. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 226 requests on ulipristal were directed to the German Embryotox institute during the study period 2010-2018. Outcomes of pregnancies exposed-(i) precycle, (ii) preconceptional or (iii) first trimester-were ascertained using standardized questionnaires. Descriptive statistics were applied. MAIN RESULTS AND THE ROLE OF CHANCE: Failed EC with UPA resulted in 95 prospectively ascertained pregnancies, of which 56 had completed follow-up: 37 live births, 7 SABs and 12 ETOPs. There was no major birth defect. Just 34% of women had taken UPA during the fertile window. Seven prospectively enrolled pregnancies were treated for myoma and had known pregnancy outcomes: five healthy live births and two SABs. Among the four retrospectively reported pregnancies after EC, there was one child diagnosed with Beckwith-Wiedemann syndrome (BWS). LIMITATIONS, REASONS FOR CAUTION: Our limited sample size does not allow concluding safety of UPA use in pregnancy. WIDER IMPLICATIONS OF THE FINDINGS: We provide a preliminary basis for reassuring women who wish to carry their pregnancy to term after EC or myoma treatment with UPA. However, because of the report of a BWS after UPA exposure, a possible epigenetic effect could not be excluded and requires further evaluation.