Stretch marks are skin lesions that appear on certain women, generally during puberty or pregnancy.
Their form: they look like lines or streaks on the skin.
Their size: a stretch mark can be between half a centimeter and several centimeters long and between 1 millimeter and 1 centimeter wide.
Their appearance: they are smooth and taut upon appearance and gradually take on a furrowed, crumpled appearance when they have finished forming.
Their colour: stretch marks gradually change from pink to red to purple when they are forming and then fade to silvery-white over time.
Their number: this can vary enormously, but stretch marks nearly always appear in clusters of several parallel lines in an often symmetrical arrangement.
Their location: this can also vary, but the most affected areas tend to be the abdomen, hips, buttocks, inside thighs and breasts.
Their duration: once appeared, stretch marks never completely disappear. They fade and lighten in colour over time before taking on their definitive appearance of silvery-white stria.