Can Emergency Contraceptives Affect Breastfed Infants?

Emergency contraception—commonly known as the “morning-after pill”—is a safe and effective option for preventing pregnancy after unprotected intercourse or contraceptive failure. For lactating individuals, a frequent concern is whether these medications pose any risk to the breastfeeding infant.

Current evidence from major health authorities—including the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and the American College of Obstetricians and Gynecologists (ACOG)—indicates that emergency contraceptive pills containing levonorgestrel (a progestin-only formulation) are compatible with breastfeeding. Levonorgestrel has low oral bioavailability in infants, minimal transfer into breast milk, and no documented adverse effects on infant growth, development, or feeding behavior.

Ulipristal acetate, another emergency contraceptive agent, is also considered acceptable during lactation by WHO and ACOG, though data are more limited. If used, a brief 24-hour interruption of breastfeeding may be advised by some clinicians as a precautionary measure—though this is not universally required and should be weighed against the benefits of continued nursing.

It is important to note that combined estrogen-progestin emergency contraceptives are not recommended for use during lactation due to potential suppression of milk supply and insufficient safety data regarding estrogen exposure in infants.

Healthcare providers should counsel lactating patients about timing, dosing, and reassurance regarding infant safety—emphasizing that routine breastfeeding need not be discontinued following appropriate emergency contraceptive use. Shared decision-making, individualized risk assessment, and access to ongoing contraceptive counseling remain essential components of postpartum reproductive care.