Stretch marks, medically known as striae distensae, are common dermal scars that result from the rapid stretching of the skin. They form when the connective fibers within the dermis layer rupture due to mechanical stress or hormonal changes. While most people associate stretch marks with a flattened or slightly sunken appearance, the presence of a distinct raised or bumpy texture is a specific concern. This elevation suggests that the skin’s natural healing process has either become exaggerated or that another dermatological issue is coinciding with the mark’s location.
Understanding Normal Stretch Mark Formation
Stretch marks begin when the skin is pulled beyond its capacity to stretch, causing a tear in the collagen and elastin support structures found in the dermis. This rapid tissue expansion is often associated with growth spurts, pregnancy, or significant weight fluctuations. The body registers this dermal tear as a wound and initiates a repair process, which leads to scar tissue formation.
Initially, these marks are often red, pink, or purplish, a stage known as striae rubrae, which indicates active inflammation and increased blood flow to the area. During this phase, the marks can sometimes feel slightly raised or swollen due to the inflammatory response and edema in the dermis. Over time, the blood vessels constrict and inflammation subsides, leading to the mature, chronic stage called striae albae. These older marks are typically white or silvery and are often atrophic, meaning they appear slightly sunken or depressed, which is the normal texture of a mature stretch mark.
The Main Culprit: Hypertrophic and Keloid Scars
The most common reason a stretch mark develops a persistent bump is an abnormal healing response involving the overproduction of collagen. Instead of a typical sunken scar, the body’s fibroblasts produce an excessive amount of fibrous tissue to repair the dermal tear. This aggressive healing leads to a permanent, raised texture.
The type of raised scar determines its characteristics, with hypertrophic and keloid scars being the two main categories. A hypertrophic scar is raised and often firm to the touch, but it remains confined to the boundaries of the original stretch mark. These scars may be red or pink and can sometimes soften and flatten naturally over months or years as the collagen remodels.
Keloid scars represent a more aggressive form of abnormal healing, characterized by a dense, rubbery texture and growth that extends beyond the original stretch mark borders. Unlike hypertrophic scars, keloids rarely regress spontaneously and can continue to grow indefinitely, sometimes becoming painful or itchy. Individuals with a genetic predisposition, a family history of keloids, or darker skin tones have a higher risk of developing this pathological scarring.
Other Causes for Raised Texture
Separate dermatological conditions can also create bumps located within the stretch mark area. Folliculitis, an inflammation or infection of the hair follicles, can cause small, red, pus-filled bumps that resemble acne. Since hair follicles are present where stretch marks occur, these inflamed bumps can appear directly on the mark, creating localized, temporary roughness.
In rare cases, a bump might be an acne nodule or cyst, which forms deep under the skin when pores become clogged with oil and dead skin cells. These hard, painful lumps are distinct from the underlying scar tissue but their presence contributes to a raised texture. These incidental bumps require a different treatment approach than the stretch mark itself and may be worsened by common stretch mark creams.
Treatment and When to Consult a Dermatologist
A persistent, raised bump on a stretch mark warrants a consultation with a dermatologist for an accurate diagnosis, especially to differentiate between a hypertrophic scar and a keloid. You should seek medical advice if the bump is rapidly increasing in size, becomes painful, begins to bleed, or shows signs of infection like pus or warmth. A professional can also confirm that the bump is not a sign of a more serious, unrelated dermatological condition.
Treatment for raised stretch marks focuses on reducing the excess collagen and flattening the tissue. Corticosteroid injections are a first-line therapy, involving the direct injection of a steroid into the scar tissue to help soften and flatten the raised area. Laser therapy, such as pulsed dye laser, is often used to target blood vessels and reduce the redness and thickness of the scar.
For persistent or aggressive bumps like keloids, treatment focuses on flattening the tissue. Options include:
- Cryotherapy (freezing).
- Surgical removal, often followed by radiation or steroid treatment to prevent regrowth.
- Non-invasive home treatments like silicone sheets or gels, applied for several months.
- Microneedling, a professional option that stimulates controlled collagen remodeling.