Stretch marks are long, narrow streaks, stripes, or lines that develop on the skin. They occur when the skin is suddenly stretched and are extremely common.
Anyone can develop stretch marks, although they tend to affect more women than men.
They can occur on a range of body parts, including the stomach, thighs, hips, breasts, upper arms, and lower back.
This type of scarring happens when the skin cannot resume normal form after a period of intense growth, often due to pregnancy, weight gain, weight loss, or puberty. Over 50 percent of women experience stretch marks during pregnancy.
Fast facts on stretch marks
- Stretch marks are long, narrow streaks or stripes that occur when the skin is stretched too quickly.
- Pregnancy, puberty, and rapid weight gain can all cause stretch marks.
- There is little medical evidence available confirming the effectiveness of current treatments for stretch marks.
- Stretch marks often fade over time without treatment and do not pose any serious long-term health risks.
Stretch marks are scars or disfiguring lesions. They are also called striae, striae distensae (SD), striae atrophicans, and striae gravidarum.
The most common areas affected include:
Stretch marks are not physically dangerous but can cause problems with self-image and anxiety. For some people, stretch marks are a significant cosmetic concern that can affect day-to-day living.
Before stretch marks begin to emerge, the skin can appear thin and pink. It may also feel irritated or itchy.
The marks initially develop as wrinkly, raised streaks that can be red, purple, pink, reddish-brown or dark brown, depending on skin color. The streaks eventually fade and flatten and tend to change to a silvery color over time.
Stretch marks may gradually become less noticeable, but this can often take years.
Extreme skin growth or shrinkage can cause stretch marks.
Common causes of skin stretching include:
- Pregnancy: Between 50 and 90 percent of women who are pregnant experience stretchmarks during or after birth.
- Puberty: Rapid growth is typical in young people going through puberty. This can lead to stretch marks.
- Rapid weight gain: Putting on a lot of weight in a short space of time can cause stretch marks.
- Medical conditions: Certain conditions can cause stretch marks, such as Marfan syndrome and Cushing's syndrome. Marfan syndrome can lead to decreased elasticity in the skin tissue, and Cushing's syndrome can lead the body to produce too much of a hormone that leads to rapid weight gain and skin fragility.
- Corticosteroid use: Prolonged use of corticosteroid creams and lotions can decrease levels of collagen in the skin. Collagen strengthens and supports the skin, and a reduced amount can increase the risk of stretch marks.
The skin consists of three key layers. Stretch marks form in the dermis, or middle layer, when the connective tissue is stretched beyond the limits of its elasticity. This is normally due to rapid expansion or contraction of the skin.
As the body grows, the connecting fibers in the dermis slowly stretch to accommodate slow growth. However, rapid growth leads to sudden stretching. This causes the dermis to tear, allowing deeper layers of skin to show through.
This can form stretch marks and contributes to the way they look.
Stretch marks eventually fade to a silvery, white, or glossy appearance, due to the pale fat beneath the skin becoming visible instead of the usual blood vessels.
They are more likely to develop and become more severe where there are high levels of circulating cortisone, or when cortisone is applied to the skin. Cortisol, the stress hormone produced by the adrenal glands, is converted into cortisone. This weakens elastic fibers in the skin.
A number of risk factors have been associated with the development of stretch marks, but the evidence varies. More research is needed to confirm the causes of stretch marks.
The risk factors for developing stretch marks could be linked to:
- family history
- chronic diseases
- body mass index (BMI) before pregnancy
- birthweight of the child in women who are pregnant
These findings can be explained by the greater degrees of skin stretching in obese women with larger babies, and by age-related changes in skin collagen and connective tissue that affect the likelihood of tearing.
Stretch marks are easily diagnosed based on a skin examination and a review of a person's medical history.
The doctor will usually ask questions based on signs and symptoms, as well as any medications currently being used or existing medical conditions.
Stretch marks are not harmful and do not cause medical problems. In rare cases, they may indicate an underlying medical issue that requires treatment or monitoring.
Treatment for stretch marks can be costly and is not always effective.
Unless an underlying condition is the cause, it is unlikely that your insurer will fund treatment. Stretch marks are seen as a cosmetic complaint.
Creams, gels, lotions, and cosmetic surgery have all been proposed as treatments for stretch marks, although there is little medical evidence to support the effectiveness of such treatments.
Current treatments are particularly limited in their ability to deliver long-lasting improvements for all skin types.
Stretch marks often fade over time and become unnoticeable. For women who develop stretch marks in pregnancy, these usually become less noticeable around 6 to 12 months after giving birth.
Makeup can be used to conceal stretch marks on more exposed areas of the body while they are more pronounced.
Creams, oils, and topical preparations
There is no high-quality evidence that applying lotions, creams, or oils to the skin can help the appearance of stretch marks.
Topical treatments are preparations containing active ingredients that are applied to the surface of the skin.
Several studies have compared the effects of topical treatments to preparations containing no active ingredients, or to the effects of receiving no treatment at all.
These investigations found no statistically significant difference between the groups, suggesting that currently available treatment options do not enhance or speed up the healing process of stretch marks.
Stretch marks cannot always be prevented. However, the following steps may help to reduce the risk:
- Maintain a healthy weight.
- Avoid yo-yo dieting.
- Eat a balanced diet rich in vitamins and minerals. Consuming a suitable amount of vitamins A and C can help support the skin, as well as the minerals zinc and silicon.
- Aim for slow and gradual weight gain during pregnancy.
- Drink six to eight glasses of water every day.
Stretch marks can be unsightly, but they are a common and often temporary problem.
They pose no long-term health risks, and treatment is normally intended to improve the self-image of the person with stretch marks.