Stretch marks are caused by glucocorticoid hormones that affect the epidermis by preventing the fibroblasts from forming collagen and elastin fibers which are responsible for keeping skin taut. This causes a lack of support within the skin, leaving it vulnerable to stretching and dermal and epidermal tearing. If skin is subjected to more stretching force than it can handle, a tear occurs. A combination of genetic influence and hormonal changes influence a person’s skin capacity for withstanding stretching force. Diet and exercise may also affect the skin’s ability to stretch without tearing.
During Pregnancy: The majority of women (75-90 percent) develop stretch marks during pregnancy. The hormonal levels that occur around the sixth or seventh month (primarily during the third trimester) are when most women’s skin is subjected to higher stretching force. Diet seems to be the only factor that can be controlled with regards to the production of stretch marks.
Although cocoa butter is often recommended to help prevent and treat stretch marks, it has not been clinically proven effective in either case.
Medical Review: Gauri Khurana, MD, (01/10)