Can You Breastfeed After Taking Emergency Contraception?

Women who are breastfeeding and require emergency contraception face important clinical considerations. According to current evidence-based guidelines from the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and the Academy of Breastfeeding Medicine (ABM), levonorgestrel-based emergency contraceptive pills (ECPs) are considered compatible with breastfeeding.

Levonorgestrel, a progestin-only compound, is minimally excreted into breast milk—typically less than 1% of the maternal dose—and poses no known risk to the nursing infant. Pharmacokinetic studies show rapid maternal clearance and negligible accumulation in milk, supporting its safety during lactation.

In contrast, ulipristal acetate—a selective progesterone receptor modulator—is not recommended for use during breastfeeding due to insufficient safety data. Its longer half-life and unknown transfer kinetics into human milk warrant caution; clinicians should advise against its use until further evidence becomes available.

It is important to emphasize that emergency contraception does not interfere with milk production or composition. No adjustment in feeding frequency or timing is required after taking levonorgestrel ECPs. However, women should be counseled that ECPs do not protect against sexually transmitted infections and are not intended for routine contraceptive use.

Clinicians should also discuss reliable ongoing contraception options—such as progestin-only pills, intrauterine devices (IUDs), or implants—as part of post–emergency contraception counseling, particularly given the heightened risk of unintended pregnancy during the early postpartum period.