Most women develop stretch marks on their abdomen during pregnancy, however it is also common to get them on the breasts, thighs, hips, lower back and buttocks. While they can appear anywhere on the body, they are most likely to appear in places where large amounts of fat are stored.
Stretch marks are actually tiny tears in the supporting layers of tissue under your skin as it's pulled tight to the limit during pregnancy. Whether or not you get them has a lot to do with genetics: Chances are, if your mother had them, you probably will too, but if she sailed through her pregnancies with smooth skin intact, you'll likely follow suit. Rapid pregnancy weight gain can also make you more prone to getting stretch marks. And darker-skinned women are less likely to have stretch marks than those who are fair-skinned (plus they're not as visible on dark skin).
What Can I Do About Stretch Marks When I'm Pregnant?
Though stretch marks are usually genetic, there are a few ways to try to minimize their appearance:
* Moisturize. Cocoa butter certainly won't hurt, though no stretch mark cream is a miracle cure. If nothing else, moisturizing daily will help with the dryness and itchy skin associated with pregnancy (plus it's fun to have your partner rub some onto your tummy!).
* Nourish your skin from the inside. Plenty of vitamin C foods in your pregnancy diet may also help keep your skin toned and less subject to stretch marks.
* Watch your weight. Keep an eye on that scale during pregnancy and put your pounds on slowly and steadily instead of in big spurts. Keep in mind that eating for two doesn't mean literally eating twice as much, so as much as possible, try to follow the general recommendations for caloric intake during pregnancy.
* Wait it out. Of course you wanted a solution yesterday, but hold off for now. Your dermatologist can offer treatments such as Retin-A or laser therapy after you give birth. Neither is safe during pregnancy, however, and the stretching ain't over till it's over.
Source: https://www.whattoexpect.com/pregnancy/symptoms-and-solutions/stretch-marks.aspx