Stretch marks most commonly appear during the third trimester of pregnancy, typically around weeks 25 to 30, when the belly is growing most rapidly. Some women notice them earlier in the second trimester, and a smaller number develop them only in the final weeks before delivery. About 50 to 90 percent of pregnant women develop stretch marks to some degree, making them one of the most common skin changes during pregnancy.
Why the Third Trimester Is Peak Time
Stretch marks form when skin stretches faster than its underlying structure can keep up with. During the third trimester, the baby gains the most weight and the uterus expands dramatically, putting the skin of the abdomen under significant mechanical stress. The middle layer of skin, which contains the collagen and elastic fibers responsible for keeping skin firm, literally tears under that tension. Those small tears are what you see on the surface as stretch marks.
Hormonal shifts amplify the problem. Pregnancy hormones like cortisol and estrogen change the composition of the skin’s connective tissue, making it more vulnerable to tearing even before the stretching peaks. This is why some women notice marks appearing on their breasts or hips as early as the second trimester, when hormonal changes are well underway but the belly hasn’t fully expanded yet.
Where They Show Up First
The abdomen is the most common location, but stretch marks frequently appear on the breasts, hips, thighs, and buttocks as well. Breast-related marks sometimes show up earlier than abdominal ones because breast tissue begins growing and changing in the first and second trimesters in preparation for milk production. On the belly, marks tend to start below the navel and can spread outward and upward as the third trimester progresses.
New stretch marks typically look pink, red, or purplish depending on your skin tone. On darker skin, they may appear darker than the surrounding skin or have a slightly purple hue. On lighter skin, they tend to start as bright pink or reddish-purple lines. Over time, after pregnancy, they fade to a lighter, silvery color that blends more with the surrounding skin.
Who Is More Likely to Get Them
Genetics plays the biggest role in whether you’ll develop stretch marks and how severe they’ll be. If your mother had significant stretch marks during pregnancy, your chances are higher. Beyond family history, several other factors increase risk:
- Younger maternal age. Women who are pregnant in their teens or early twenties tend to develop more pronounced marks, likely because their skin hasn’t yet lost elasticity from aging but paradoxically seems more reactive to the hormonal changes of pregnancy.
- Higher pregnancy weight gain. Gaining weight rapidly or gaining more than the recommended range puts extra mechanical stress on the skin.
- Carrying a larger baby or multiples. A bigger uterus means more stretching, which means more opportunity for tears in the skin’s connective tissue.
- Higher pre-pregnancy BMI. Starting pregnancy at a higher weight is associated with increased stretch mark severity.
- Previous stretch marks. If you had them from puberty growth spurts or a previous pregnancy, you’re more likely to develop them again.
Skin hydration and baseline skin elasticity also matter, though these are harder to measure or control. Some women with no obvious risk factors still develop extensive marks, while others with multiple risk factors get very few. The genetic component is strong enough that no amount of prevention guarantees clear skin.
Can You Prevent Them?
The honest answer is that no cream, oil, or treatment has been definitively proven to prevent stretch marks during pregnancy. That said, keeping skin well-moisturized may reduce itching and could modestly help with severity. Products containing ingredients like hyaluronic acid or centella asiatica (a plant extract common in many stretch mark creams) have shown limited positive results in some small studies, but nothing conclusive enough to call them reliable prevention.
Cocoa butter and olive oil are among the most popular home remedies, but clinical trials have not found them effective at preventing stretch marks compared to using no product at all. The ritual of applying them isn’t harmful, and the moisturizing effect can help with the intense itching that often accompanies rapidly stretching skin in the third trimester.
The most evidence-backed approach to minimizing stretch marks is managing weight gain during pregnancy. Gaining weight gradually and within the range your provider recommends reduces the speed at which skin has to stretch, which lowers the chance of those connective tissue tears. This isn’t about restriction. It’s about steady, consistent gain rather than rapid spikes.
How They Change After Delivery
Fresh stretch marks that are still red or purple are considered “immature” and are in their most treatable phase. Over the six to twelve months following delivery, most marks gradually fade on their own as the inflammation settles and the broken collagen fibers reorganize. They won’t disappear completely, but they typically become much less noticeable, fading to thin, pale lines that sit slightly below the level of the surrounding skin.
For women who want to speed up the fading process, treatments like topical retinoids (not safe during pregnancy or breastfeeding, but an option afterward) can improve the appearance of newer marks. Laser therapy and microneedling have also shown results in clinical settings, particularly when started while marks are still in the red or purple stage. Once marks have turned white or silver, they’re harder to treat, though laser options can still improve texture and visibility to some degree.
The timeline varies widely from person to person. Some women find their marks fade significantly within a few months postpartum, while others still notice prominent lines a year or two later. Skin tone, mark severity, and genetics all influence how quickly and completely the fading happens.
Early Signs to Watch For
Before visible lines appear, many women notice intense itching on the abdomen, breasts, or hips. This itching often signals that the skin is being stretched to the point where marks are about to form. The skin in those areas may also feel thinner or look slightly shiny. These early signs are most common in weeks 20 to 28, right before and during the period when marks typically become visible.
Not all pregnancy itching means stretch marks, though. Severe, persistent itching, especially on the palms and soles of the feet, can indicate a liver condition called intrahepatic cholestasis of pregnancy, which requires medical attention. If your itching is widespread, intense, or accompanied by other symptoms, it’s worth bringing up at your next prenatal visit rather than assuming it’s just stretching skin.