The World Health Organization recommends a two-year interval between deliveries before pregnancy, which is beneficial to both the mother and the perinatal child. If another pregnancy occurs within a short period of time after delivery, because the time is too short and the mother’s body has not fully recovered, then the pregnancy will have many pregnancy complications and a high rate of cesarean section, especially cesarean section scar pregnancies, which pose a huge safety risk to the mother. At the same time, the risk of preterm labor, poor fetal development, and perinatal mortality are all relatively high. Research shows that the rate of unwanted pregnancy within one year after delivery is as high as 20% Postpartum contraception is very important and easy to ignore. When to start contraception after delivery? Because it is difficult to accurately estimate the time for each woman to resume ovulation after delivery, it is important to start contraception for the first time after delivery. Contraceptive methods include: 1. Contraceptive ring, suitable for 42 days after a flat birth and six months after a cesarean section. If menstruation is not resumed after delivery, pregnancy needs to be ruled out before the ring can be put on, and ultrasound needs to be done to understand the thickness of the uterine lining, if the lining reaches more than 8mm, it is best to wait until after menstruation to put on the ring. 2.Short-acting oral contraceptive pills: for those who are breastfeeding, they should be used half a year after delivery; for those who are not breastfeeding, they should be used 3 months after delivery. 3.Condoms: need to be worn throughout. The failure rate of contraception is high, so it is not routinely recommended. 4, tubal ligation: contraceptive effect is good, but irreversible, with the full opening of two children, do not advocate tubal ligation.