Stretch marks, also known medically as striae, are streak-like lines that can develop on the surface of the skin. The most commonly affected areas are the stomach, thighs, buttocks and breasts. Stretch marks are caused by sudden stretching of the skin.
This can occur as a result of pregnancy, rapid weight gain and growth spurts during puberty. Stretch marks often start off as red or purple streaks that gradually fade to silvery-white lines in the skin. Stretch marks occur in the dermis, the middle layer of skin.
The dermis contains fibres called collagen and elastin which help to keep the skin supple and allow the skin to stretch as your body grows. However, if the skin is stretched suddenly over a short period of time the fibres over-stretch and break causing the dermis to tear. The tears in the dermis allow the blood vessels in the deeper layers of skin to show through. This is what gives stretch marks the red or purple colour when they first appear. Eventually the exposed blood vessels contract and only the fat beneath which is pale in colour, will show through causing the stretch marks to fade to the silvery-white colour.
People with more collagen in their skin are less likely to develop stretch marks. Stretch marks are very common in both men and women. Around 8 out of 10 pregnant women are affected by stretch marks. Not only is your skin stretched to its limit, the production of special hormones during pregnancy can make you more likely to develop stretch marks. Specialised hormones designed to soften the ligaments in your pelvis to make giving birth easier also soften the fibres in the skin making you prone to stretch marks. Women are more likely to develop stretch marks if their mother has stretch marks. Rapid weight gain and yo-yo dieting can also lead to stretch marks. By regularly dieting your weight goes up and down quickly without giving your skin enough time to adjust. You should aim to lose weight slowly to prevent your skin from stretching too quickly. Boys and girls often undergo growth spurts (when you grow very quickly in a short amount of time) during puberty. This sudden growth can cause the development of stretch marks. People with darker skin are less likely to have stretch marks.
Laser treatments for stretch mark
Two different laser treatments are used to reduce the appearance of stretch marks. When stretch marks are red or purple the IPL (intense pulsed light) laser can be used to reduce the redness and decrease any associated inflammation. For stretch marks that have faded to the silvery-white colour, the Fractional laser resurfacing is preferred.
The Fraxel treatment uses patented fractional technology to target damaged skin with microscopic laser columns that penetrate deep into the skin. The laser causes minor injuries in the skin called microtrauma. The microtrauma created by the laser stimulates the production of collagen which helps to replenish the lost collagen in the stretch marks and helps to reduce imperfections. The Fractional laser resurfacing treatment causes the stretch marks to become narrower and gives the skin a smoother appearance.