Melasma is often associated with the female hormones estrogen and progesterone. It is especially common in pregnant women, women who are taking birth control pills (oral contraceptives) and women taking hormone replacement therapy (HRT) during menopause.

Sun exposure is also a strong risk factor for melasma. The condition is particularly common in tropical climates resulting in a uniform brown color usually seen over the cheeks, forehead, nose, or upper lip. It is most often symmetrical (matching on both sides of the face).