ICEC shares new evidence on safety of EC pills in ongoing pregnancies

The International Consortium for Emergency Contraception shared an updated summary of studies on the theme of safety of EC pills in ongoing pregnancies. We hope you find it useful for your work.

“Evidence continues to accrue confirming that emergency contraceptive pills (ECPs) do not harm a developing fetus if they are mistakenly taken early in an ongoing pregnancy. In ICEC’s 2010 “Fact Sheet on the safety of levonorgestrel-alone emergency contraceptive pills (LNG ECPs)” (published jointly by the World Health Organization, UNFPA and IPPF and available in English, French and Spanish), we cited two studies that found that LNG ECPs have no effect on the developing fetus if the contraceptive fails and pregnancy occurs. Studies by De Santis et al. in 2005¹ and Zhang et al. in 2009², which compared pregnancy outcomes in women who used LNG ECPs during their conception cycle with women who had not used LNG ECPs, found no difference in rates of miscarriage, birth weight, malformations, or in the sex ratio at birth between the two groups.

The longitudinal study designed by Zhang et al has now produced further results. The children born in the original study have now been followed for two years after birth, and results show that that children who were exposed in utero to LNG ECPs exhibit normal development.  Over a two-year period the authors found no statistically significant differences between the 195 children who were exposed to LNG ECPs and the 214 children who were not with respect to children’s weight, height, head circumference, and intelligence scores.³

In addition, growing evidence shows that ulipristal acetate (UPA) ECPs also will not harm an ongoing pregnancy. HRA Pharma, the manufacturer of UPA (sold under brand names such as ella and ellaOne), recently published its post-marketing surveillance data combined with data from its clinical trials.  Although few pregnancies and fewer live births occurred, the 28 live births that did occur have been followed, and results reported in an article by Levy, et al. Rates of miscarriage and pregnancy and delivery complications were normal, and one fetal anomaly was identified that was determined not to be related to UPA exposure in utero. ⁴

All available evidence to date supports the safety of LNG and UPA EC, and indicates that prenatal exposure to these medications does not produce birth defects or developmental delays.”

Citations

¹ De Santis M, et al. Failure of the emergency contraceptive levonorgestrel and the risk of adverse effects in pregnancy and on fetal development: an observational cohort study. Fertility & Sterility, 2005, 84:296-299.

² Zhang L, et al. Pregnancy outcome after levonorgestrel-only emergency contraception failure: a prospective cohort study. Human Reproduction, 2009, 24:1605-1611.

³ Zhang L, et al. Physical and mental development of children after levonorgestrel emergency contraception exposure: a follow-up prospective cohort study. Biology of Reproduction, 2014, 91:1-7.

⁴ Levy D, et al. Ulipristal acetate for emergency contraception: postmarketing experience after use by more than 1 million women. Contraception, 2014, 89:431-433.