Stretch marks are a kind of swelling marks and a pathological change of skin during pregnancy. The stria gravidarum is dark red or purplish red in the early stage, gradually appears depigmentation and skin atrophy after half a year to one year after delivery, and finally appears white or silver stripes stably.

Stretch marks are mainly distributed in the abdomen, but also in the chest, back, buttocks and proximal limbs. The occurrence of stretch marks is very common among women. Once it happens, it can last for life and bring great psychological burden to pregnant women.