After giving birth to a baby, due to different hormone levels and breastfeeding methods, the recovery time of menstruation varies from person to person. Under normal circumstances, most women will resume menstruation in about 18-20 weeks because lactation produces a large amount of lactogen, which suppresses the female endocrine system and causes the ovaries to remain in a state of suppression for a long period of time and not ovulate. However, some women, especially those who are exclusively breastfeeding, may not have menstruation for the whole period of breastfeeding, and their menstruation will resume only when the estrogen will gradually return to the normal level after the breastfeeding period is over. For women who are not breastfeeding after delivery, menstruation will come around 6-8 weeks after delivery, and if they are not producing enough breast milk or mixed breastfeeding, the recovery time of menstruation will be relatively earlier. In addition, mothers must pay attention to rest after delivery, avoid heavy physical labor, ensure adequate nutritional intake, and take contraceptive measures if they have sex during this period.