Approximately 90% of pregnant women develop stretch marks, typically appearing around the sixth or seventh month of pregnancy. They most commonly show up on the abdomen, chest, hips, thighs and buttocks as the body expands to accommodate a growing baby. While they are a normal part of many pregnancies, understanding why they form and what can reduce their development gives expectant mothers the best possible foundation for protecting their skin.

Stretch marks initially appear as purple or red streaks and gradually fade to white, gray or a tone lighter than the surrounding skin after childbirth. How visible they are and how quickly they fade depends largely on skin type, genetics and how well the skin is supported throughout pregnancy.

What actually causes stretch marks to form

Stretch marks develop when the skin stretches faster than it can maintain its natural elasticity. Beneath the surface, this process involves the breakdown of collagen and the deterioration of elastic tissue in the middle layer of the skin, known as the dermis. When rapid weight gain or physical expansion occurs over a short period, the skin’s structural support system cannot keep pace, and the resulting tears in the deeper layers of skin become visible as marks on the surface.

Hormonal changes play a significant role as well. By the third month of pregnancy, the body’s endocrine system undergoes substantial shifts, with the fetus and placenta secreting increased levels of progesterone and estrogen. These hormones stimulate melanin production and affect skin pigmentation, which is why stretch marks can darken over time and why some women also develop dark spots during pregnancy.

The skin is made up of three layers, the outer epidermis, the middle dermis and the inner hypodermis. Sustained stretching during pregnancy gradually reduces the dermis’s capacity to bounce back, making moderate, controlled weight gain one of the most practical tools for limiting mark development. Healthcare providers generally suggest aiming for a total weight gain of approximately 7 to 15 kilograms throughout pregnancy, though individual recommendations vary based on starting weight and overall health.

Who is most at risk

Not every pregnant woman develops stretch marks, and the degree to which they appear varies considerably from person to person. Several factors influence individual risk.

Genetics is one of the strongest predictors. Women whose mothers or sisters developed stretch marks during pregnancy are significantly more likely to experience them as well. Skin structure and elasticity are largely inherited, meaning that hereditary factors play a determining role regardless of how carefully a person manages their weight or skincare routine.

Age also matters. Women who are under 20 or over 35 face elevated risk, since very young skin is still developing while older skin has begun to lose some of its natural elasticity. Women who developed stretch marks during puberty are also more likely to develop them during pregnancy, as the skin has already demonstrated a tendency to mark under rapid growth conditions.

Carrying multiples increases the risk further because the abdomen must expand more significantly than in a single-baby pregnancy, placing greater stress on the surrounding skin over a shorter period.

Prevention strategies that can make a real difference

While no approach guarantees the complete prevention of stretch marks, several evidence-supported strategies can meaningfully reduce their appearance and help the skin recover more quickly after childbirth.

Starting early is important. Marks typically begin to appear during the second trimester, which means preventive habits ideally begin in the first trimester rather than after the first signs appear. Building skin-supporting nutrition into the diet from the beginning of pregnancy helps increase elasticity from the inside out. Foods rich in vitamin E, vitamin A, omega-3 and omega-6 fatty acids, as well as antioxidant-rich options like strawberries, blueberries and spinach, support the skin’s structural health throughout pregnancy.

Hydration plays a meaningful supporting role. Drinking adequate water daily keeps skin cells moist and supple, maintaining the flexibility the skin needs to accommodate physical changes. Well-hydrated skin is more resilient and tends to recover more quickly postpartum.

Regular, pregnancy appropriate exercise supports healthy skin by improving circulation and helping maintain a steady rate of weight gain rather than rapid fluctuations. Walking, prenatal yoga and swimming are widely recommended options that support both skin health and overall wellbeing without placing undue stress on the body.

Topical care matters as well. Applying natural oils and moisturizers consistently to areas prone to stretching, including the abdomen, hips, chest and thighs, helps keep the skin’s outer layers hydrated and more flexible. Gentle exfoliation supports skin renewal, and applied to exposed areas protects against additional pigmentation changes during outdoor activity.

Choosing skincare products carefully during pregnancy is also worth considering, as some conventional ingredients may not be recommended during gestation. Opting for gentle, natural formulations reduces the risk of irritation or unnecessary chemical exposure during a period when the skin is already more sensitive than usual.

The second trimester requires the most attention

Most stretch marks appear around the second trimester, which is also when other significant pregnancy milestones require monitoring, including gestational diabetes screening, comprehensive fetal development assessments and awareness of preterm labor signs. Managing weight gain thoughtfully during this period, staying consistent with skincare habits and keeping up with scheduled prenatal appointments addresses multiple aspects of maternal health simultaneously.

For women carrying multiples or those with a history of preterm birth or miscarriage, additional vigilance during the second trimester is particularly important. Speaking with a healthcare provider about individualized skincare and weight management strategies ensures that any approach is appropriate for the specific circumstances of the pregnancy.