- Stretch marks are caused when the second of the skin's three layers, called the dermis, is stretched so far that it loses elasticity. The damage done to the dermis is visible through the thin, outer layer of the skin and at first appears red due to tiny broken blood vessels. It then fades to a whitish color as permanent scarring occurs. Stretch marks are lighter than the rest of the skin because the stretching that causes the markings interrupts the production of collagen and the cells that produce pigmentation. Cortisone also contributes to stretch marks because its production is bad for the elasticity of skin.
- Stretch marks often appear on the hips and breasts of girls and the shoulders and upper arms of boys. Pregnant women frequently experience the appearance of stretch marks on their bellies, and all women can experience stretch marks on their breasts, buttocks and thighs. Men typically experience stretch marks on their upper bodies and abdomens.
- Children and adolescents typically see stretch marks as a result of growth spurts. When children shoot up in height or development of a specific area of their bodies, such as the breasts or shoulders, the skin often does not have enough time to grow with the body. The majority of pregnant women experience stretch marks on one or multiple areas of their body due to the amount of weight gained during such an abbreviated period. Men who lift weights and work to increase their upper body strength and muscle size often experience stretch marks across their shoulders and upper arms. Additionally, anyone who gains weight, especially to the point of obesity, is at high risk for stretch marks on many areas of the body.
- There is no way to prevent stretch marks through the use of lotions or creams. Limiting weight gain does prevent some stretch marks, but only those directly related to excessive weight. Once a stretch mark is formed, a tretinoin cream may be used soon after the stretch mark first appears to reduce the appearance. However, this form of treatment doesn't work for stretch marks that are more than six weeks old. Other treatments that break down the damaged skin (such as microdermabrasion) and encourage the growth of new skin cells and pigmentation, such as various forms of laser therapy, are helpful for the improvement in appearance of older stretch marks. No over-the-counter lotions and creams have been proven to decrease their appearance.
- Stretch marks that appeared during adolescence soften in appearance and look more like the normal skin tone over time. Other stretch marks may lessen in appearance as the stretched area decreases in size, such as with post-pregnancy weight loss, but remain unless treated. Because treatments for stretch marks are expensive, not covered by insurance and don't guarantee the complete disappearance of the marks, most choose to live with their stretch marks rather than pursue treatment.
