Stretch marks are a visible phenomenon in the subcutis, which are caused by strong stretching of the tissue, usually due to pregnancy or drastic weight loss/gain. In medical terminology, the stretch marks on the skin are referred to as striae cutis atrophicae or striae cutis distensae (from the Latin striae = stripe, cutis = skin, atrophicae = atrophic, distensae = overstretched). In the context of pregnancy, the appearance of stretch marks is physiological; they are called stretch marks (striae gravidarum). The lines appear red or purple at first because the blood vessels beneath the dermis show through. The marks eventually fade to a white or silvery colour once the blood vessels have contracted. There a various treatment offers to help reduce the appearance of stress marks.