Stretch marks during pregnancy may be related to hormone levels, age, genetic factors and so on The etiology of stretch marks is still unclear and may be related to changes in skin tone during pregnancy and changes in hormone levels. Low maternal age, family history of stretch marks, special body skin, high maternal basal weight, and rapid maternal weight gain are risk factors for stretch marks in pregnant women. Stretch marks usually begin to appear in the 6th or 7th month of pregnancy and are mainly characterized by purple or pink stripes. Six to 12 months after delivery, they begin to decolorize and atrophy, and stretch marks gradually evolve into linear scar-like stripes. Severe stretch marks during pregnancy can be treated by going to the hospital and using appropriate methods under the guidance of a doctor, and paying attention to controlling weight gain may be useful in reducing stretch marks.