Combined hormonal contraceptive use among breastfeeding women: an updated systematic review

Limited evidence of poor to fair quality demonstrates an inconsistent impact of COCs on breastfeeding duration and success. The evidence also demonstrated conflicting results on whether early initiation of COCs affects infant outcomes but generally found no negative impact on infant outcomes with later initiation of COCs. The body of evidence is limited by older studies using different formulations and doses of estrogen and poor methodologic quality. Given the significant limitations of this body of evidence, the importance of contraception for postpartum women and the theoretical concerns that have been raised about the use of combined hormonal contraception by women who are breastfeeding, rigorous studies examining these issues are needed. In addition, postpartum women should be counseled about the full range of safe alternative contraceptive methods, particularly during the first 6 weeks postpartum when the risk of venous thromboembolism is highest and use of estrogen may exacerbate this risk.