Stretch marks can appear when there is rapid stretching of the skin. They are often associated with the abdominal enlargement of pregnancy. They can be found in children who have become rapidly obese. They may also occur during the rapid growth of puberty in males and females. Striae are most commonly located on the breasts, hips, thighs, buttocks, abdomen, and flank.
Stretch marks appear as parallel streaks of red, thinned, glossy skin that over time become whitish and scar-like in appearance. The stretch marks may be slightly depressed and have a different texture than normal skin.
Striae may also occur as a result of abnormal collagen formation, or a result of medications or chemicals that interfere with collagen formation. They may also be associated with longtime use of cortisone compounds, diabetes, Cushing disease, and post-pregnancy.