Stretch marks are fuchsia or pink stripes in the early stages, which can gradually change to white or silver stripes with time. Stretch marks are skin expansion lines that appear on the skin of pregnant women. Their formation may be related to changes in hormone levels, changes in skin tension, genetic factors, weight gain during pregnancy, etc. They are commonly found on the abdomen, legs, buttocks and other parts of pregnant women. Stretch marks appear in the 6th or 7th month of pregnancy, initially appearing as purplish-red or pink stripes, and with the prolongation of time, will gradually appear pigment loss, skin atrophy, and ultimately the formation of white or silvery scarring stripes, and the local skin may also be accompanied by itching sensation.