Safety data for levonorgestrel, ulipristal acetate and Yuzpe regimens for emergency contraception
The World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC) provide recommendations for use of emergency contraceptive pills (ECPs), including levonorgestrel (LNG) and combined oral contraceptives (COCs). A new ECP formulation, ulipristal acetate (UPA), is now available worldwide. To determine whether LNG, UPA or COC (Yuzpe) ECPs are safe for women with certain characteristics or medical conditions, we searched the PubMed and Cochrane databases for articles published from date of inception until May 2015 pertaining to the safety of LNG, UPA or Yuzpe ECP use. For direct evidence, we considered studies that looked at safety outcomes among women with certain medical conditions or characteristics taking ECPs compared with women not taking ECPs. For indirect evidence, we considered studies that reported pharmacokinetic (PK) data for ECP use among women with certain medical conditions or characteristics and studies that reported safety outcomes among healthy women taking ECPs. Five studies provided direct evidence; of these five studies, four examined LNG or Yuzpe use among pregnant or breastfeeding women, and one reported risk of ectopic pregnancy among women repeatedly using LNG ECPs. Poor pregnancy outcomes were rare among pregnant women who used LNG or Yuzpe ECPs during the conception cycle or early pregnancy. Breastfeeding outcomes did not differ between women exposed to LNG ECP and those unexposed, and there was no increased risk of ectopic pregnancy versus intrauterine pregnancy after repeated use of LNG ECPs compared with nonuse. Forty-five studies provided indirect evidence. One PK study demonstrated that LNG passes into breastmilk but in minimal quantities. In addition, nine studies examined pregnancy outcomes following ECP failure among healthy women, and 35 articles reported adverse events. Studies suggest that serious adverse events are rare among women taking any of these ECP formulations.Evidence on safety of ECPs among women with characteristics or medical conditions listed within WHO and CDC family planning guidance is limited. However, both direct and indirect evidence for our study question did not suggest any special safety concerns for the use of ECPs among women with particular medical conditions or personal characteristics, such as pregnancy, lactation or frequent ECP use.