Stretch marks develop on the skin when the skin is rapidly stretched over a short periods of time. The most common situations in which we see stretch marks include growth spurts during adolescence, rapid weight gain, and pregnancy. There are also a few medical conditions which can lead to stretch marks. Pulsed-dye laser has been used to help diminish the red to violaceous color seen in new stretch marks. Old stretch marks which are white in color do not improve with laser treatments.