Why do I have stretch marks?

What happens beneath the skin?

Rapid stretching or shrinking can break collagen and elastin, the proteins that support your skin. The resulting scars are stretch marks, also called striae. This happens below the surface, rather than being just a change in skin colour. Not everyone develops stretch marks during the same body changes. Hormone fluctuations seem to play a role, and having relatives with stretch marks increases your risk.345

What makes stretch marks more likely?

• Puberty can bring growth spurts that stretch the skin quickly.
• Pregnancy stretches the belly as the baby grows and the breasts as they enlarge in preparation for breastfeeding.
• Rapid weight gain or loss can cause stretch marks.
• Rapid muscle growth during weight training can cause stretch marks.
• Some steroid creams or tablets can cause stretch marks, particularly with prolonged use.

During pregnancy, stretch marks often appear on the belly, but they can also develop on the breasts, hips and buttocks. They can look red, brown or purple and usually become less noticeable after delivery. Avoiding excessive pregnancy weight gain can reduce the risk, but lotions and oils cannot reliably prevent the marks. Getting stretch marks does not mean you missed a necessary skincare step.6

Why do I have stretch marks on my thighs?

The legs are a common place for stretch marks, alongside the hips, bottom, belly, breasts, chest, upper arms and back. Thigh stretch marks can follow the same rapid growth or weight changes that cause marks elsewhere. Their location alone does not identify the cause: puberty, pregnancy and recent body changes are more useful clues.2

Is it normal to have stretch marks?

Yes. Stretch marks are very common, particularly around periods of growth and body change. They can be pink, red, brown, black, purple or silver, so they do not look identical on every skin tone. They usually start darker and become lighter with time.2

Is it okay to have stretch marks?

Yes. Stretch marks themselves are harmless, and treatment is optional. If their appearance bothers you, treatment can make them less noticeable rather than erase them. You can also leave them alone and allow them to fade naturally.2

Why does my child have stretch marks?

A puberty growth spurt is a common explanation. Breast development can also stretch the skin quickly enough to cause marks, and puberty is the most common reason for breast stretch marks. Family tendency can help explain why one child develops them while another does not. Stretch marks can happen as part of growing up, rather than only after pregnancy or major weight gain.4

Will stretch marks go away?

New stretch marks can be slightly raised and itchy. As they mature, their colour fades and they can become slightly sunken, with a more wrinkled surface. Older marks can look whitish or silver. Fading is not the same as disappearing: older stretch marks are harder to treat and cannot usually be cleared completely. There is no fixed timetable for natural fading.45

Do creams and oils help?

Most stretch mark creams have little evidence behind their promises, despite the considerable confidence printed on the jar. Cocoa butter has not been shown to prevent stretch marks or reduce their appearance. Coconut oil, olive oil and shea butter are not effective stretch mark treatments either. Moisturising can still keep skin comfortable; after pregnancy, creams and oils can feel soothing even when their effect on the marks is minimal.237

Prevention is not always possible. Maintaining a healthy weight can reduce your chance of developing stretch marks. Products containing centella or hyaluronic acid may help prevent them, but neither is a dependable way to avoid marks during growth or pregnancy.25

What can make stretch marks less noticeable?

Early marks are the better treatment target. Hyaluronic acid and prescription tretinoin can make new stretch marks less noticeable; retinol can also help fade early marks. In one study, people applying tretinoin every night for 24 weeks had less noticeable stretch marks. That is a treatment timescale, not a promise that every mark will respond. A dermatologist can help choose an option based on your health, age and how long you have had the marks.5

How should I try a topical treatment?

1. 1Check suitability first. Do not use retinoid creams during pregnancy, and ask your doctor before treating stretch marks while breastfeeding.
2. 2For retinol, test a small patch of skin and wait a couple of days to check for redness or itching.
3. 3Follow the product instructions or prescription directions. General retinol guidance is to start slowly, at bedtime, rather than immediately using it every day.
4. 4Gently massage a suitable stretch mark cream into early marks and use it consistently. Visible improvement takes weeks, not a few applications.

Retinol can cause dryness, redness, peeling, itching or burning and increases sensitivity to sunlight. Use sunscreen on exposed treated skin. Sensitive skin or a tendency to allergies can make retinol a poor choice. A patch that becomes very red or itchy is a reason not to move straight to wider application. Facial retinol directions are not a body treatment dose; use the directions for your chosen product or prescription.1

Dermatologists also use lasers, chemical peels, microdermabrasion, radiofrequency and ultrasound. Procedures can improve appearance but cannot remove stretch marks completely, even when the appointment sounds more impressive than the cream. Several sessions or combined treatments can be needed for older marks. Lasers can cause burns or changes in colour on darker skin, so choose a dermatologist experienced with your skin tone and discuss risks and costs before booking.45

Do not tan to hide stretch marks. Scars do not tan, so tanning can make the contrast more obvious while exposing skin to sun damage. Self tanner can temporarily camouflage both new and older marks.35

When should I see a doctor?

See a GP if you have large stretch marks together with more fat on your chest and belly but slim arms and legs, fat around the back of your neck and shoulders, or a red, puffy, rounded face. This combination can indicate Cushing's syndrome, a condition involving too much cortisol. Stretch marks alone do not mean you have it.24

During pregnancy, persistent itching without a rash needs a call to your maternity clinician rather than being assumed to come from stretch marks. It can indicate cholestasis, a pregnancy condition that needs medical assessment. Ask your doctor before using botanical creams during pregnancy, too; a plant ingredient is not automatically suitable.36