Why do stretch marks appear on the skin?
Written by Jessica Tapia, MD
Stretch marks are colored lines that appear on the skin due to stretching of the skin. Causes of stretch marks include sudden weight changes, pregnancy, hormonal changes, corticosteroid treatments, dry skin, poor diet and genetic predisposition.
These marks may appear during pregnancy, puberty, times of rapid weight change or as a result of a medical condition.
While stretch marks never disappear completely, they generally become less noticeable as they fade to a lighter color over time.
Treating stretch marks effectively is difficult, although there is limited evidence that certain treatments can improve their appearance.
What are stretch marks?
Stretch marks are narrow, discolored lines that can appear on the skin. They are actually a type of scar that usually develops when the skin stretches rapidly, such as during puberty or pregnancy.
The most common locations for stretch marks are the abdomen, buttocks, hips and breasts, but stretch marks can appear in other places where the skin stretches quickly. Other parts of the body where they can appear include the breasts, hips, arms, legs and buttocks.
Of the entire population, it is estimated that between 11% and 88% of people are affected by stretch marks. Scars are more common among specific populations.
Most stretch marks occur in adolescents when they go through a period of rapid growth and in pregnant women when they experience rapid body changes and growth.
In fact, researchers have estimated that between 50% and 90% of people who are pregnant have stretch marks.
Stretch marks are not harmful to your physical health. However, their appearance can negatively affect some people's confidence. Research has shown that having stretch marks can cause emotional distress and reduce a person's perceived quality of life.
What causes stretch marks?
Stretch marks develop when the skin stretches rapidly, over a short period of time. When this stretching occurs, the skin's collagen and elastin break down, affecting the fibers. The breakdown of these fibers contributes to the formation of stretch marks.
Stretch marks are most likely to occur during puberty or pregnancy but can also appear in other circumstances.
You may notice stretch marks if you:
Experienced rapid weight gain
Increased your muscle mass when you exercise
Have Cushing's syndrome (when your body produces too much cortisol hormone)
Obtained breast implants
You use topical corticosteroid treatments (anti-inflammatory skin creams).
Risk factors during pregnancy
In general, having a family history of stretch marks means that stretch marks are more likely to occur on some parts of your body.
Hormonal fluctuations, such as those that occur during puberty and pregnancy, also increase the risk of developing stretch marks. Also unfortunately, as women become pregnant, they are more likely to suffer from stretch marks due to the possibility of pregnancy.
If you are pregnant, you are more likely to develop stretch marks if you have other family members with stretch marks, are younger, weigh more than recommended before or during pregnancy, or are pregnant with a large baby.
What do stretch marks look and feel like?
Stretch marks look like parallel stripes or lines on the skin.
The look and feel of your stretch marks will depend on their stage. Stretch marks go through two main phases: a pigmented (colored) phase and a discolored phase.
In the first stage, stretch marks are called striae rubrae. During this stage, the color of the stretch marks will depend on your skin tone. Stretch marks first appear as red, pink, dark brown, purple, reddish/violet or reddish brown. At this stage, stretch marks may appear raised or shiny. It is common for the skin to itch when stretched.
In the second stage, the stretch marks are called striae alba. During this stage, the stretch marks fade to a whitish color or a lighter version of your skin tone. The marks may also sink into your skin, so you will feel a minor groove when you run your hands over the area.
Do stretch marks disappear on their own?
Stretch marks do not disappear on their own. In fact, the second stage of a stretch mark, the albino stretch mark phase, is considered chronic. That means stretch marks will remain as they look and feel after fading.
While stretch marks do not disappear on their own, they can fade on their own. For some people, this fading will occur within months after the initial colored marks appear. The marks may take a year or more to fade entirely for others.
How do you remove stretch marks?
Because stretch marks are a type of scar, they cannot be removed entirely. There is limited evidence that specific treatments can help reduce the appearance of scarring. While no particular treatment is known to be more effective in reducing the severity of scarring, some treatments have more evidence of effectiveness than others.
Topical skin treatments
There are many white stretch mark removal remedies such as creams, lotions and gels that you can apply to your skin that are marketed to help minimize the appearance of stretch marks.
Some are available over-the-counter and some are available by prescription. The following treatments have some evidence of being effective for stretch marks, although they may not work for everyone and may not help all the time: Tretinoin, silicone gel, and hyaluronic acid.
Some topical treatments may not work at all. For example, no evidence exists that popular home treatments such as olive oil, vitamin E, cocoa butter, or almond oil reduce stretch marks.
Medical treatments to remove stretch marks
Your provider may perform one or more procedures to reduce stretch marks. The following procedures can help reduce the appearance of stretch marks:
Microneedling
On microneedling reduces stretch marks by creating micro-injuries in the top layer of skin to stimulate the body's production of collagen and elastin.
Most people need three to five microneedling sessions to fade stretch marks. You should see improvement after the first three. People with younger, more elastic skin will need annual maintenance treatments, while patients over 40 may need them every four to six months.
CO2 Laser
CO2 laser treatments can smooth and fade stretch marks and other scars. CO2 lasers can be fractionated, meaning they target only part of the skin, or they can be non-fractionated and fully ablative, removing the entire epidermis and heating the deeper layer. (Most modern CO2 lasers are fractionated).
Subsequently, temporary side effects include crusting and tenderness.
Depending on whether your doctor uses a fractional or traditional CO2 laser, full recovery may take a few weeks, but you will see results as soon as the scabs disappear. You may need more than one treatment for optimal results.
Other Treatments
Other treatments to remove stretch marks include retinoic acid, chemical peels, and microdermabrasion.
Your doctor will be able to recommend the best option of how to remove stretch marks depending on factors such as your age, in which area or areas they are located, the most common being the abdomen and buttocks.
“Las estrías son líneas descoloridas que aparecen en la piel debido a su estiramiento rápido, comúnmente durante el embarazo, la pubertad o cambios bruscos de peso.
Aunque no desaparecen completamente, las estrías suelen volverse menos notorias con el tiempo, y existen algunos tratamientos que pueden mejorar su apariencia, como cremas tópicas, microneedling y tratamientos láser.
Si bien no son dañinas para la salud física, las estrías pueden afectar la confianza de algunas personas.”
