stretch mark

anatomy

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

July 23, 2026

Quick Summary

Stretch marks, also known as striae, are lines that appear on the skin due to the rupture of elastic fibers. This typically occurs when the skin is excessively stretched, such as during pregnancy, rapid growth spurts in adolescence, or due to obesity.12

The skin's strength and elasticity come from collagen, a protein synthesized in the dermis. When the skin stretches beyond its capacity, the connective tissue can rupture, leading to the formation of stretch marks. Initially, these marks appear as purple lines, but over time, they fade to an ivory white color as scar tissue forms. They can appear on various parts of the body, including the abdomen, hips, breasts, thighs, buttocks, and shoulders.21

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

3 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

pregnancy
Skin
“Stretch marks,” which appear on the breasts and abdomen during pregnancy, are due to the tearing of the elastic tissues in the skin that accompanies enlargement of the breasts, distention of the abdomen, and the deposition of subcutaneous fat. They are pink or purplish red…
Read More
“Stretch marks,” which appear on the breasts and abdomen during pregnancy, are due to the tearing of the elastic tissues in the skin that accompanies enlargement of the breasts, distention of the abdomen, and the deposition of subcutaneous fat. They are pink or purplish red…
Read More

skin disease
Connective tissues
…the skin may rupture after stretching, even in healthy persons, forming purple linear discolorations. Because of the defect in the continuity of the dermal connective tissue, these striae are soft to the touch. Initially livid, after several months the striae become ivory white and firm because of the formation of…
Read More
…the skin may rupture after stretching, even in healthy persons, forming purple linear discolorations. Because of the defect in the continuity of the dermal connective tissue, these striae are soft to the touch. Initially livid, after several months the striae become ivory white and firm because of the formation of…
Read More