Striae Distensae (Stretch Marks) 

Updated: Feb 22, 2022
Author: Samer Alaiti, MD, RVT, RPVI, FACP; Chief Editor: William D James, MD 

Overview

Practice Essentials

Striae distensae, a common skin condition, do not cause any significant medical problem; however, striae can be of significant distress to those affected. Commonly called stretch marks, they represent linear dermal scars accompanied by epidermal atrophy. Striae distensae are usually a cosmetic problem; however, if extensive, they may tear and ulcerate when an accident or excessive stretching occurs.

(See the image below.)

Striae distensae in pregnancy. Baby is due in less Striae distensae in pregnancy. Baby is due in less than 2 weeks. Courtesy of Patrick Fitzgerald and Wikimedia Commons.

Approximately 90% of pregnant women, 70% of adolescent females, and 40% of adolescent males (many of whom participate in sports) have stretch marks. Striae affect adolescents, pregnant women (striae gravidarum), and patients with excessive adrenal cortical activity. Stretch marks affect persons of all races and women more commonly than men. Adolescents with striae can expect their striae to be less visible with time.

In a comparison study using 150 striae sites in 19 patients, Lin et al found polarization-sensitive optical coherence tomography (PS-OCT) to be useful for assessing striae severity when compared to visible light dermoscopy. They hypothesize this usefulness is due to the ability of PS-OCT to measure the local subsurface birefringence in tissue.[1]

Treatment with tretinoin, flashlamp pulsed dye laser, and chemical peels significantly improves the clinical appearance of early, active stretch marks.

Pathophysiology

Striae distensae affect skin that is subjected to continuous and progressive stretching; increased stress is placed on the connective tissue due to increased size of the various parts of the body. It occurs on the abdomen and the breasts of pregnant women, on the shoulders of body builders, in adolescents undergoing their growth spurt, and in individuals who are overweight.

Factors leading to the development of striae have not been fully elucidated. Striae distensae are a reflection of "breaks" in the connective tissue. Skin distention may lead to excessive mast cell degranulation with subsequent damage of collagen and elastin.[2] Prolonged use of oral or topical corticosteroids or Cushing syndrome (increased adrenal cortical activity) leads to the development of striae. Genetic factors could certainly play a role, although this is not fully understood.

In a letter to the editor of the Journal of Investigative Dermatology, Tung et al conducted genome-wide association analysis and found evidence that implicates elastic microfibrils in the development of nonsyndromic striae distensae.[3]

Oakley and Patel expound on the pathophysiology of stretch marks, asserting that origination of striae is thought to involve release of elastase due to mast cell and macrophage activity. As a result, the mid-dermis undergoes elastolysis, followed by collagen and fibrillin reorganization.[4]

 

Presentation

Physical Examination

Early striae present as flattened, thinned skin with a pink hue that may occasionally be pruritic (see the image below). Gradually, they enlarge in length and width and become reddish purple in appearance (striae rubra). The surface of striae may be finely wrinkled.

Striae distensae on the torso of a 13-year-old boy Striae distensae on the torso of a 13-year-old boy. One-day duration. Courtesy of Wikimedia Commons.

Mature striae are white, depressed, irregularly shaped bands, with their long axis parallel to the lines of skin tension (see the image below). They are generally several centimeters long and 1-10 mm wide. Gradually, some striae may fade and become inconspicuous. The natural evolution of stretch marks is similar to that of scar formation or a healing wound.

Female torso with striae distensae from pregnancy. Female torso with striae distensae from pregnancy. Courtesy of Parenting Patch and Wikimedia Commons.

In pregnancy, striae usually affect the abdomen and the breasts. In an unusual case, a 28-year-old patient at 21 weeks' gestation with systemic lupus erythematosus presented with fluid-filled blisters on the bilateral breasts and abdomen. These bullous lesions were drained and dressed. They grew no microorganisms on culture. The authors concluded that the striae were benign, despite the unusual and alarming appearance.[5]

The most common sites for striae on adolescents are the outer aspects of the thighs and the lumbosacral region in boys and, in girls, the thighs, buttocks, and breasts. Considerable variation occurs, and other sites, including the outer aspects of the upper arms, are occasionally affected.

Striae induced by prolonged systemic steroid use are usually larger and wider than other phenotypes of striae, and they involve widespread areas, occasionally including the face.

Striae secondary to topical steroid use are usually related to enhanced potency of the steroids when using occlusive plastic wraps. They usually affect the flexures and may become less visible if the offending treatment is withheld early enough.

Causes

The factors that lead to the development of striae are poorly understood. No general consensus exists as to what causes striae. One suggestion is that they develop as a result of stress rupture of the connective tissue framework. It has also been suggested that they develop more easily in skin that has a high proportion of rigid cross-linked collagen, as occurs in early adult life. This is evident in striae due to pregnancy, lactation, weight lifting, and other stressful activities. Increased adrenal cortical activity has been implicated in the formation of striae, as in the case of Cushing syndrome. Additionally, the cellular and extracellular matrix alterations that mediate the clinical phenotype of stretch marks remain poorly understood.

 

DDx

Diagnostic Considerations

Although the diagnosis of striae is usually straightforward, the rare possibility of Cushing syndrome must be entertained. In the latter, striae are characterized by their inordinate breadth, depth, and intense color.

In linear focal elastosis (elastotic striae), asymptomatic, yellow linear bands arrange themselves horizontally over the lower back. These lesions may resemble striae distensae, but they are palpable rather than depressed and yellow rather than purplish or white.

 

Workup

Histologic Findings

In the early stages, inflammatory changes may predominate; edema is present in the dermis along with perivascular lymphocyte cuffing.

In the later stages, the epidermis becomes thin and flattened with loss of the rete ridges. The dermis has thin, densely packed collagen bundles arranged in a parallel array horizontal to the epidermis at the level of the papillary dermis. Elastic stains show breakage and retraction of the elastic fibers in the reticular dermis. The broken elastic fibers curl at the sides of the striae to form a distinctive pattern.

Scanning electron microscopy shows extensive tangles of fine, curled elastic fibers with a random arrangement. This arrangement is in contrast to normal skin, which has thick, elastic fibers with a regular distribution. When viewed by transmission electron microscopy, the ultrastructure of elastic and collagen fibers in striae is similar to that of healthy skin.

 

Treatment

Medical Care

In current practice, even with the significant dermatologic advances in topical medicaments and light-based devices, total resolution of these lesions remains an unattainable goal.

Avoidance of rapid weight loss or gain may help prevent the emergence of stretch marks, especially in high-risk groups such as teenagers and expecting mothers. Adolescents with striae can expect some improvement in their striae over time.

Striae distensae are most likely to respond to pharmacologic products and clinical interventions at their early stage (striae rubra). Once they become white (striae alba), only few treatment modalities exist and they are become quite difficult to treat.

Intensive moisturization of the lesions and the use of vitamin C, fruit acids, retinols, and other pharmaceuticals have been advocated for the early treatment of striae distensae rubra.

Topical application of tretinoin has been shown to significantly improve the clinical appearance of early striae distensae (striae rubra).[6, 7, 8] It should not, however, be used in pregnant or breastfeeding females, because of a theoretical concern about its teratogenic effects. The use of other retinoids such as adapalene and tazarotene may also hold promise in the treatment of striae distensae.

Surgical Care

Al-Himadani et al correctly identified that no high-quality, randomized controlled trials evaluating treatments for striae distensae exist.[9] The following is a concise listing of available surgical modalities used in the treatment of striae distensae.

Treatment with the 585-nm flashlamp pulsed dye laser at low energy densities was shown to improve the appearance of striae.[10, 11] Multiple treatments at 4- to 6-week intervals are usually required. At a lower fluence (2-4 J/cm2), the 585-nm flashlamp pulse dye laser (FLPDL) has been purported to increase the amount of collagen in the extracellular matrix. The 585-nm FLPDL has a moderate beneficial effect in reducing the degree of erythema in striae rubra but has no apparent benefit in striae alba. Because of the potential for adverse effects, FLPDL treatments should be performed with extreme caution or even not at all in darker-skinned patients (phototypes V and VI).[12, 13, 14]

A study by Suh et al evaluated the effectiveness of using 585-nm pulsed dye laser with radiofrequency for striae distensae. Thirty-seven patients with abdominal striae distensae were treated with the Thermage and 585-nm pulsed dye laser in the first session at baseline. An additional 2 sessions of pulsed dye laser therapy were performed at weeks 4 and 8. Thermage was used at a fluence of 53-97 J/cm2, and pulsed dye laser-therapy was used at a fluence of 3 J/cm2 with a 10-mm spot. Skin biopsy specimens were taken from 9 patients.[15]

In the subjective assessment in the Suh et al study, 89.2% of the patients showed "good" and "very good" overall improvement, and 59.4% were graded as "good" and "very good" in elasticity. All of the 9 specimens showed an increase in the amount of collagen fibers, and increased elastic fibers were found in 6 specimens. The authors reported that Thermage and pulsed dye laser appear to be an effective treatment for striae distensae.[15]

In another study, involving the use of a 1064-nm long-pulsed Nd:YAG laser, Goldman et al reported subjective data (55% of patients reported excellent improvement) and objective photographic findings (40% of evaluating physicians reported excellent improvement). Minimal adverse effects were reported.[16]

Intense pulsed light, a noncoherent, nonlaser, filtered flashlamp that emits a broadband visible light, has been reported to yield clinical and microscopic improvement in striae distensae. It seems to be a promising treatment modality with minimal adverse effects and little-to-no down time. Its efficacy in the treatment of photodamaged facial skin has been widely reported; it promotes the production of neocollagen and elastic fibers.[17]

A study by Shokeir et al found that both pulse dye laser and intense pulse light can enhance the clinical picture of striae through collagen stimulation.[18]

A randomized pilot study by Hexsel et al found superficial dermabrasion to be as effective as topical tretinoin on early striae distensae. Additionally, superficial dermabrasion had a lower frequency of adverse effects and better adherence of the patients.[19]  Another study, by Ferreira et al, found that 10 treatments of galvano-puncture or dermabrasion produced similar satisfactory results on striae appearance.[20]  

Most of the enhancements in the treatment of striae pertain to striae rubra; only very limited modalities have shown promise in improving the appearance of striae alba. Lasers and light sources emitting UV-B irradiation (eg, the 308-nm excimer laser) have been shown to repigment striae distensae (striae alba). The improvement is due to an increase in melanin pigment, hypertrophy of melanocytes, and an increase in the number of melanocytes.[10]

In another study, a 1550-nm fractional photothermolysis laser was investigated for the treatment of striae distensae alba in Asian patients. Significant improvement in the appearance of the stretch marks was observed 2 months after treatment. Histologic examination revealed a substantial increase in epidermal thickness as well as collagen and elastic fiber deposition. Minimal pain and posttreatment hyperpigmentation were the main adverse events reported. Fractional photothermolysis laser treatments appear to improve the appearance of striae distensae alba, particularly through repetitive treatments.[21]

Pertaining to the use of carbon dioxide ablative fractionated lasers in the treatment of striae distensae, Alexiades-Armenaka et al found that the treatment gives rise to unpredictable results. "The data were inconclusive regarding the treatment of striae distensae following a series of treatments, with some patients demonstrating significant improvement while others showed no change from baseline."[22] On the other hand, other authors found benefit of using fractional photothermolysis via fractional carbon dioxide laser for treatment of striae alba.[23, 24]

Yang et al reported that nonablative fractional photothermolysis and ablative carbon dioxide fractional laser resurfacing are equally effective and safe treatment modalities for striae distensae in skin of Asian persons. However, neither treatment showed any greater clinical improvement than the other treatment.[25]  In a comparison of fractional carbon dioxide laser and carboxytherapy, both modalities produced significant reductions in striae dimensions and similar patient satisfaction.[26, 27]

Ryu et al reported on the efficacy of combination therapy of fractionated microneedle radiofrequency and fractional carbon dioxide laser as a safe treatment protocol with a positive therapeutic effect on striae distensae.[28]

In a study of 25 adults who received 1-3 microneedling treatments, there was at least 50% improvement in all striae. No permanent adverse effects were reported.[29]

Obagi et al had good success using low concentrations (15-20%) of trichloroacetic acid and performing repetitive papillary dermis-level chemexfoliation. The peels can be repeated at monthly intervals, with improvement in skin texture, firmness, and color.[30]

In a systematic review and network meta-analysis of common striae distensae treatments, Lu et al found bipolar radiofrequency combined with topical tretinoin to have the best clinical effectiveness and patient satisfaction ratings at 84.5% and 95.7%, respectively.[31]

 

Medication

Medication Summary

Drugs of choice should have the ability to improve the skin texture and color, to remodel the collagen in the dermis, and to promote elastin synthesis.

Retinoid-like Agents

Class Summary

Topical retinoids have been shown to be beneficial in remodeling hypertrophic scars and in improving the clinical appearance, including improvement of the surface texture, fine and coarse wrinkling, skin color, and laxity, of photoaged skin after 3-6 months of therapy.

Tretinoin topical (Avita, Retin-A, Atralin, Renova)

Trans-retinoic acid is a derivative of vitamin A (retinol), effectively used to treat acne vulgaris and other disorders of keratinization for the past 3 decades. Exhibits a certain degree of vitamin A growth-promoting activity; however, it is not stored in the body as retinol and its esters. Rather, it is metabolized rapidly and mostly excreted in bile. When administered topically, a minute amount passes through dermis but has not been detected systemically.

In epithelial cells, affects differentiation, neoplastic transformation, tumor promotion, collagen synthesis, wound healing, stimulation and modulation of immune response, inflammation, cell membranes, and many other processes.

0.05% strength has been shown to improve hypertrophic scars. Postulated that this is due to effect on fibroblasts (ie, decreased fibroblast proliferation and decreased fibroblast collagen synthesis). Effect on fibroblasts is mediated through specific binding receptor proteins. Topical application significantly improves clinical appearance of early, active stretch marks. Processes responsible for clinical improvement remain unknown.

Patients are instructed to gradually increase amount of tretinoin until mild erythema and exfoliation develops; may also apply a bland emollient if excessive irritation develops.