Stretch marks are areas of skin where the deep dermis, located between the epidermis and the hypodermis, has torn spontaneously. When they appear, they have the form of streaks resembling scars in length, purplish red in color, and are inflammatory. They lighten over time to become white and pearly, almost the same color as the skin. They can appear during pregnancy, during significant and sudden weight gain or loss, and during adolescence.