Stretch marks during pregnancy

By trimester

Weeks 1–13

1st trimester

Stretch marks are uncommon this early, since most appear as the belly grows faster later in pregnancy. Keeping skin moisturized is a reasonable habit, though the research on whether it changes your odds of developing them is mixed.

Weeks 14–27

2nd trimester

This is when stretch marks most often start, commonly from around 24 weeks as the abdomen stretches quickly. Younger age, a family history of stretch marks, and faster weight gain are the risk factors research has identified most consistently.

Weeks 28–birth

3rd trimester

Existing stretch marks may keep stretching and deepen in color as your belly reaches its largest size. They typically start fading from reddish-purple toward lighter, less noticeable lines in the weeks and months after delivery.

What does the evidence show for stretch marks?

• Striae distensae (stretch marks) are commonly observed in pregnancy, with studies reporting a range of about 43% to 88% of pregnant people affected, and they typically fade from reddish or purple lines to paler, flatter lines over time, though they rarely disappear completely. 1
• One study following pregnant participants found stretch marks affected 70% to 90% of women, most often on the abdomen, breasts, buttocks, and thighs, with lesions commonly first appearing around the 24th week of pregnancy. 2
• A study of Chinese primiparous women identified younger maternal age, greater weight and BMI gain during pregnancy, and a positive family history, the single most significant factor, as independent risk factors for stretch marks, most of which appeared between 24 and 35 weeks. 3
• Another study similarly found younger maternal age and greater pregnancy weight gain associated with developing stretch marks, and found no significant link to skin type or the use of topical creams, even though most participants had tried one. 4
• A Cochrane review cited in a pilot trial protocol found no high-quality evidence supporting the use of any topical oil or cream to reduce the development of stretch marks, even though a large majority of pregnant women try one anyway. 5

When should I call my provider about stretch marks?

Ordinary stretch marks can be mildly itchy while they're still reddish, but that itch usually stays limited to the stretch marks themselves and eases as they fade. Widespread, intense itching, or raised, hive-like bumps that spread beyond the stretch marks, especially in the third trimester, fits the pattern of PUPPP or cholestasis of pregnancy more than ordinary stretch-mark itch, and is worth a call to your provider; see our guides to itchy skin and cholestasis for that distinction. When in doubt, call your obstetric team the same day. Early input almost always beats waiting, and the on-call line exists exactly for this.