Stretch marks

Stretch marks are narrow lines that develop when the skin stretches or changes quickly. Their medical name is striae distensae. They are common during puberty, pregnancy, weight change, and periods of rapid muscle growth.

The marks form in the dermis, the deeper layer of skin that provides strength and flexibility. Rapid growth, hormones, and inherited differences in skin structure can disrupt collagen and elastin. These are proteins that help support the skin.

New stretch marks may be red, pink, purple, or dark brown, depending on your skin tone. Over time, they usually become paler and slightly indented. They do not mean that the skin is unhealthy, and they are not contagious.

Stretch marks matter mainly because some people dislike how they look or feel self-conscious about them. They usually cause no physical harm. Treatments may make them less noticeable, but no treatment can reliably remove them completely.

Stretch marks often begin as long, irregular lines. New marks may be:

• Red, pink, purple, reddish-brown, or dark brown
• Slightly raised or swollen
• Mildly itchy or irritated
• Several centimetres long and grouped close together

As they mature, they often become white, silver, or lighter than the surrounding skin. The surface may feel thin, soft, wrinkled, or slightly sunken. Stretch marks usually do not tan in the same way as nearby skin, so they may become more noticeable after sun exposure.

Where they appear often reflects the reason for the skin change. Common locations include the abdomen, breasts, hips, thighs, buttocks, upper arms, lower back, and shoulders.

During pregnancy, they are especially common on the abdomen and breasts. Puberty-related marks may appear on the thighs, hips, back, breasts, or shoulders. Marks linked to rapid muscle growth often develop around the shoulders and upper arms.

Stretch marks themselves should not cause severe pain, open wounds, pus, or fever. Those symptoms suggest another skin problem.

Stretch marks develop when the skin's support tissue cannot adjust fully to rapid growth or stretching. Hormones also affect how collagen and elastin are produced and repaired.

Common situations linked with stretch marks include:

• Growth spurts during puberty
• Pregnancy, particularly as the abdomen and breasts enlarge
• Rapid weight gain or loss
• Fast muscle growth, including through bodybuilding
• A family tendency to develop stretch marks
• Longer-term or excessive corticosteroid exposure

Corticosteroids like prednisone or hydrocortisone are medicines that reduce inflammation. They include some creams, tablets, injections, and inhaled treatments. Strong corticosteroid creams can thin the skin when used too often, for too long, or in areas where they were not intended to be used. Prescribed corticosteroids should not be stopped suddenly without medical advice.

Rarely, broad or rapidly appearing purple stretch marks can be associated with Cushing syndrome, a condition caused by too much cortisol in the body. Other possible signs include easy bruising, muscle weakness, facial rounding, and increased fat around the abdomen or neck.

Not everyone whose skin changes quickly develops stretch marks. Genetics, age, hormone levels, and the natural strength and elasticity of the skin all play a part. Stretch marks are not caused by poor hygiene or scratching.

Stretch marks can usually be identified by examining their colour, texture, shape, and location. Tests are not normally needed when they appear during pregnancy, puberty, or an expected period of body change.

A clinician may ask when the marks began, how quickly they appeared, and whether your weight or body shape recently changed. It is also useful to mention corticosteroid creams, tablets, injections, or other steroid medicines.

Further assessment may be appropriate if the marks are unusually broad, appear suddenly without an obvious reason, or occur with symptoms such as easy bruising or muscle weakness. Depending on the findings, blood, urine, or saliva tests may be used to check cortisol levels. These tests look for an underlying hormone condition rather than confirming ordinary stretch marks.

A skin sample, called a biopsy, is rarely necessary. It may be considered only when the appearance is unusual and another skin condition needs to be excluded.

Stretch marks do not need treatment for health reasons. Many become less noticeable over months or years. Treatment is an option if their appearance bothers you, but results are often partial.

Moisturizers may ease dryness or itching. They do not remove established marks. Camouflage makeup and self-tanning products can reduce the colour difference temporarily. Sun protection may also limit contrast between the marks and surrounding skin.

Topical tretinoin, a prescription retinoid related to vitamin A, may modestly improve some early red or purple stretch marks by encouraging collagen production. It is less likely to help older pale marks. It can irritate the skin and is not used during pregnancy. If you are breastfeeding, discuss its use with a qualified clinician.

Several skin procedures are used to make stretch marks less noticeable, including:

• Laser or light treatment
• Microneedling, which creates tiny controlled skin injuries
• Radiofrequency treatment, which uses energy to heat deeper skin
• Microdermabrasion, which exfoliates the skin surface

Different lasers target redness, pigment, or skin texture. Microneedling and radiofrequency aim to stimulate new collagen. More than one session is often needed, and complete removal should not be expected.

Possible effects include temporary redness, swelling, discomfort, bruising, and changes in skin colour. Some treatments carry a greater risk of lighter or darker patches in people with darker skin tones. An experienced dermatology professional can explain which options are suitable for a particular skin type and how realistic the likely improvement is.

Cosmetic treatment can be expensive and may not be covered by health insurance or public health services. Before paying for treatment, ask what outcome is likely, how many sessions may be needed, and what side effects are possible.

Ordinary stretch marks do not damage muscles or internal organs. They do not become cancerous, spread between people, or prevent the skin from working normally.

The main effect can be emotional. Visible marks may affect confidence, body image, clothing choices, or comfort with intimacy. These feelings can be significant even though the marks are medically harmless.

Treatment can sometimes cause complications such as irritation, scarring, infection, or lasting pigment changes. The risk depends on the procedure, the equipment used, skin tone, and the experience of the person performing it.

Rarely, stretch marks are a sign of excessive corticosteroid exposure or an underlying hormone condition. In that situation, the concern is the cause rather than the marks themselves.

Stretch marks cannot always be prevented. Pregnancy, puberty, genetics, and necessary body changes cannot be controlled completely.

Creams and oils are often marketed for prevention during pregnancy. Cocoa butter, olive oil, almond oil, and vitamin E have not been shown to prevent stretch marks reliably. Moisturizing may make tight or itchy skin feel more comfortable, but it cannot guarantee that marks will not form.

Gradual weight change may reduce sudden strain on the skin, but it does not prevent every case. During pregnancy, weight and nutrition should be managed according to maternity advice rather than in an attempt to avoid stretch marks.

Use corticosteroid creams and other steroid medicines only as directed. Do not apply someone else's prescription or use a strong cream for longer than advised. Do not stop prescribed steroid tablets suddenly because this can cause serious withdrawal effects.

Stretch marks usually change more in colour than in size. Early red, purple, or brown marks may remain noticeable for several months. They then tend to become flatter, paler, and less prominent. The final colour may be white, silver, or lighter than the surrounding skin.

The slight indentation or change in texture may remain permanently. Treatment can soften the contrast or texture, but it cannot restore the skin exactly to how it looked before.

Existing stretch marks do not normally keep spreading on their own. New marks may appear if the body goes through another period of rapid growth, pregnancy, weight change, muscle gain, or corticosteroid exposure.

They do not limit exercise, pregnancy, work, sexual activity, or other parts of daily life. There is no need to protect them from ordinary movement. If rubbing or dryness causes discomfort, a plain moisturizer and comfortable clothing may help.

How noticeable the marks remain differs from person to person. Their location, original colour, skin tone, age, and cause all influence how they mature. If their appearance continues to affect your confidence, support for body-image concerns can be as worthwhile as cosmetic treatment.

Stretch marks caused by expected growth or pregnancy do not usually need medical assessment. A routine appointment may be helpful if you are unsure what the lines are or want to discuss treatment options.

Arrange a routine medical review if:

• Many marks appear suddenly without pregnancy, puberty, or clear body change
• The marks are unusually broad or deep purple
• You also have easy bruising, marked muscle weakness, or major body-shape changes
• You have been using corticosteroid medicines, especially strong skin creams
• The marks or concerns about appearance are affecting your wellbeing

Do not stop a prescribed corticosteroid suddenly while waiting for advice.

Seek urgent, same-day care for severe pain, rapidly spreading redness, warmth, pus, blistering, or fever. These are not features of uncomplicated stretch marks and may indicate infection or another skin condition.

Stretch marks alone are not an emergency. They do not normally require emergency department care.

Do stretch marks ever go away completely?

They usually fade, but they often do not disappear completely. Mature marks may remain as pale, slightly indented lines. Treatments can sometimes make them less noticeable rather than erase them.

Are purple stretch marks dangerous?

Purple, red, or brown colouring is common in newer stretch marks. Sudden broad purple marks without an obvious cause deserve a routine assessment, especially if you also have easy bruising or muscle weakness.

Does losing weight remove stretch marks?

No. Weight loss does not remove marks that have already formed. Their colour may fade naturally, although changes in body shape can make them look more or less noticeable.

Can creams prevent stretch marks during pregnancy?

No cream or oil has been shown to prevent them reliably. Moisturizers can reduce dryness or itching, but genetics, hormones, and the degree of skin change still play major roles.

Does scratching cause stretch marks?

No. Scratching does not create stretch marks, although new marks can feel itchy. Scratching hard may irritate or damage the skin surface.

Can tanning hide stretch marks?

A natural or artificial tan may make them more obvious because mature stretch marks often tan less than surrounding skin. A self-tanning product can temporarily reduce the contrast without ultraviolet exposure.