Stretch marks appear at different times from person to person, usually in the middle to late stages of pregnancy, around 6-7 months of pregnancy. There are also pregnant women who do not have stretch marks throughout their pregnancy. Stretch marks are a kind of skin swelling lines that occur on the abdomen, waist, thighs and breasts during pregnancy, and they occur in pregnant women with dark skin color, higher pre-pregnancy body mass index, high birth mass of babies, and those who are pregnant for the first time, and not all pregnant women will have stretch marks. Stretch marks usually begin to appear in the middle and late stages of pregnancy, around 24 weeks of gestation, most of which have no conscious symptoms and generally do not require special treatment. Stretch marks may fade with time after delivery, and whether they can disappear completely varies from person to person. Pregnant women do not need to be overly alarmed by the appearance of stretch marks during pregnancy, do not worry too much about it, you should maintain a relaxed mood during pregnancy, develop good habits, pay attention to personal hygiene and dietary safety.