Where do stretch marks appear during pregnancy?

It’s a wide range, but anywhere from 50 to 90 percent of pregnant women experience stretch marks, making it almost inevitable despite the aisles full of stretch mark creams out there.¹ Stretch marks in pregnancy usually appear on a woman’s abdomen, breasts, and thighs, but they can appear anywhere the body experiences weight gain. The marks usually appear in the sixth and seventh months of pregnancy (but there are exceptions), and they occur more often in a woman’s first pregnancy than in subsequent ones.

There are a ton of products that claim to help prevent stretch marks during pregnancy, the most popular being Bio-Oil, but there aren’t enough medical studies that prove they work.² “The most important thing is to gain weight slowly,” says Dr. Shirley Chi, a board-certified dermatologist at the Center for Advanced Dermatology in Arcadia, CA. “The slower you can gain weight during pregnancy, the better off you're going to be.”

What’s interesting is that “the older you are when you're pregnant, the less stretch marks women tend to have,” says Dr. Chi, “because your skin is already looser.” (As the skin ages, it produces less collagen and elastic and becomes less taut, less likely to tear when stretched.)

References:
^1,2The use of anti stretch marks’ products by women in pregnancy: a descriptive, cross-sectional survey by Miriam Brennan et al. BMC Pregnancy Childbirth.