Despite renewed interest in postpartum family planning programs, the question of when women should start contraception after a birth remains unanswered. Three indicators of postpartum unmet need consider women to be fully exposed to the risk of pregnancy at different times: right after delivery, after six months of amenorrhea, and at the end of amenorrhea. While the protection afforded by postpartum abstinence and lactational amenorrhea lowers unmet need, women often rely on these methods without actually being protected. Programs should acknowledge these methods’ widespread use and inform women about their limits. Also, programs should test the respective advantages of targeting the postnatal period, the end of six months of amenorrhea/exclusive breastfeeding, or the resumption of sexual intercourse as the best time to offer contraceptive services.