It is difficult to recover after delivery because the body has undergone major physiological changes during pregnancy and childbirth. During pregnancy, women are in great physical demand and often feel hungry. The pregnant mother's body will store extra fat to meet the nutritional needs of the fetus. However, these fats will not disappear immediately after production, and it takes time to gradually reduce them. When a woman is pregnant, the uterus will continue to expand, which may lead to the stretching and relaxation of abdominal muscles. This will make it more difficult to restore a flat abdomen. After pregnancy and delivery, the hormone level in the body will change greatly, which may affect weight control and metabolism, making it more difficult to lose weight. It takes a lot of time and energy to take care of the newborn after delivery. After delivery, the mother reduces the time of exercise and pays attention to diet. Lifestyle makes the body recover more slowly.