Stretch marks appear in the second to fourth months of pregnancy. Stretch marks are caused by changes in hormone secretion in the body, and the increased secretion of estrogen and progesterone in the body after pregnancy can easily cause body pigmentation. The length and shade of the stretch marks of each person will be different, some pregnancy stretch marks are not obvious is normal, stretch marks are about half a year after delivery can disappear on their own, some people pigmentation is more serious, stretch marks disappear time will also be extended. After pregnancy, pay attention to eat more vegetables, fruits, reasonable supplement vitamins, pay attention not to eat spicy and stimulating food, and not often stimulate the skin, can reduce skin pigmentation.