Overview Progestin-Only Pill Use and Breastfeeding Study Status: Recruiting Trial end date: 2022-06-30 Target enrollment: Participant gender: Summary This study will assess the impact of early initiation (less than one week postpartum) and delayed initiation (4 weeks postpartum) of two types of progestin-only contraceptive pills (POPs) on maternal, breastmilk, and infant outcomes. Phase: Phase 4 Details Lead Sponsor: University of California, San DiegoTreatments: Contraceptive AgentsProgestins