Stretch Marks: Common Causes, How They Form & How To Treat Them

Stretch marks are common and can affect both men and women, however they are more frequent among women and usually occur at one’s thighs, buttock, lower back, chest, upper arm and knee. Although they rarely cause medical problems, stretch marks are considered a major aesthetic concern and may be distressing to some individuals. In this article, we will discuss the causes of stretch marks, how they form, and the treatment options available.

What exactly is a stretch mark?

A stretch mark is a type of scar that develops when our skin stretches or shrinks quickly. The abrupt change causes the collagen and elastin that supports our skin, to rupture. As the skin heals, stretch marks may appear. When stretch marks first appear, they tend to be red, purple, pink, reddish-brown, or dark brown, depending on one’s skin colour. Early stretch marks may feel slightly raised and can be itchy while over time, the colour fades and the narrow bands sink beneath your skin. If you run your finger over a mature stretch mark, you can feel a slight depression.

Causes of stretch marks

Stretch marks occur typically during pregnancy, puberty, obesity or certain medical conditions e.g. Cushing syndrome. Other triggers include hormonal imbalance, extended periods of mechanical stretch or any structural changes to the skin can lead to stretch marks. Chronic use of oral or topical corticosteroids can also contribute to the development of marks.

Stretch marks can form via three main mechanisms:

Genetic predisposition

No specific gene has been identified as the cause of marks developing on the skin. However, stretch marks have been identified among identical twins, families and inherited genetic skin conditions, suggesting genetic predisposition, that certain individuals may have a greater tendency of developing stretch marks based on their genes.

Hormones

A hormonal imbalance can contribute to the development of stretch marks. A hormone called adrenocorticotrophic causes an increased rate of protein breakdown, hence less collagen and elastin fibres are produced and the skin is less flexible and resilient to withstand stretching, causing marks to form. This effect is similar to that caused by corticosteroids, which explains why chronic use of the drug is more prone to developing stretch marks.

Mechanical stretch

Rapid expansion or contraction of the skin causes it to stretch beyond its usual elastic ability. Fibres in the middle skin layer stretch to accommodate when growth is slow. However, with sudden stretching, the dermis may tear, causing the deeper skin layers to be seen and forming marks.

Who is more prone to stretch marks?

One who is undergoing puberty and has growth spurts, pregnant women, one who undergoes rapid weight loss or gain or is weight training and experiencing rapid muscle growth. Those who apply a corticosteroid to their skin for a long time can also cause stretch marks. Individuals who have Cushing’s disease or Marfan syndrome may also see stretch marks.

It is important to have your stretch marks reviewed by your dermatologist, as there are a few medical conditions which may mimic these marks. Like any scar, stretch marks are permanent, but treatment helps to make them less noticeable. Consulting an accredited dermatologist would help you in seeking an effective treatment. In addition, there are also specific treatments which should only be performed by a qualified dermatologist to reduce the appearance of these marks.

How to treat stretch marks

Topical treatments only have mild effects in reducing the appearance of stretch marks. Still, many patients prefer non-laser approaches, thus topicals remain as a common approach. It is recommended to use products on early stretch marks as in general, early stretch marks respond better to treatment than the older lesions. 

Tretinoin

Tretinoin is a retinoid, helping to boost fibroblast production, which are molecules responsible for the structural support in our cells and synthesize collagen, hence helping to make early stretch marks less noticeable. In one study, people who applied this prescription cream every night for 24 weeks had less noticeable stretch marks while those who didn’t apply the cream saw their early stretch marks grow. It is not recommended to use tretinoin during pregnancy as it carries a risk of birth defects

Phytochemicals

Plant extracts such as Centella Asiatica can boost the cells that produce elastic fibers and collagen. Researchers have found that products containing centella may help prevent stretch marks. Resveratrol, naturally occurring in grapes and berries, can also boost skin elasticity. Elixir-V™ Total Recovery Serum contains a potent combination of phytochemicals, including resveratrol, to help fight ageing effects.

The Elixir-V™ Total Recovery Serum contains intensely nourishing concentrate of deep hydrating, lifting and tightening peptides for the perfect V-face look.

Moisturizers

A randomized, double-blind, placebo-controlled study in pregnant women showed that the severity of stretch marks can be reduced by topical application of moisturisers. Radiance Fluide™ Hydrating Emulsion, a dermatologist-designed lightweight moisturizer formulated with niacinamide, helps stimulate collagen synthesis, tighten and lift stretch marks. The Radiance Emulsion formula is recommended for use with Qraser Custom Cut Mask, uniquely engineered with several properties which are beneficial for creating a healthy skin microenvironment, and helping the balance of growth factors that stimulate collagen production. 

The Radiance Fluide™ Hydrating Emulsion contains LARECEA™ Extract for regeneration and skin brightening ingredients for a dewy glow. Specially formulated for a light-weight feel to impart a radiant glow without make-up.

Procedures that dermatologists perform: 

Chemical peels

They help to induce the production of collagen and improve the appearance of stretch marks. Salicylic acid, lactic acid and glycolic acid are most commonly used.

Microdermabrasion

In this process, a targeted injury is caused to trigger collagen production and to deposit elastin. Topical therapies are also more effective after microdermabrasion, as your active ingredients can better penetrate the dermis layer. In a study conducted, microdermabrasion was found to be as effective as the daily application of topical 0.05% tretinoin cream in the reduction in the severity of early stretch marks.

Learn more about microdermabrasion in our podcast, Dermatologist Talks: Science of Beauty Ep 43, where accredited dermatologist Dr. Teo Wan Lin discusses the benefits of microdermabrasion, as well as how it works.

Light therapy

Different types of light treatment are also available to stimulate collagen production in the dermis layer. Examples include infrared light devices, intense pulsed light (IPL) and ultraviolet light.

Ablative lasers

Such lasers are effective in reducing scars as they create a deliberate wound to induce healing of the skin. The treatment of stretch marks using the laser showed clinical improvement, with the laser inducing the formation of collagen. There are rarely complications, and the cooling of the stretch marks before and immediately after the use of the laser further helps to protect the skin. 

References:

Wollina U, Goldman A. Management of stretch marks (with a focus on striae rubrae). J Cutan Aesthet Surg. 2017;10(3):124-129. doi:10.4103/JCAS.JCAS_118_17