Stretch marks are scarred areas that form in the skin when it is overstretched. This leads to the formation of reddish and whitish scars.
Stretch marks are also called striae or striae distenae. They are scar-like lines that form when the skin stretches too much or too quickly, and are seen when one has fast growth or weight change. Stretch marks are very common and seen in 70% of teenage girls and 40% of teenage boys. Approximately 75% of the pregnant women will develop stretch marks. They are also more common in Caucasians.