Melasma is a unique pigmentation condition whereby patches of abnormal pigmentation appear over areas of the face. The severity and placement of the pigmentation varies from individual to individual.
Typical areas where melasma appears are the forehead, above the upper lip and across the cheeks. Unlike pigment disorders that are a direct result of sun exposure such as solar letigos, which appear as brown distinct round patches, melasma tends to manifest as brown pigment that spreads out over a larger area of skin. Melasma can appear shadow-like or as distinctive patches with defined borders. Exposure to ultraviolet light can darken and exacerbate melasma-associated pigmentation.
Melasma is commonly referred to as pregnancy mask. This is due to the shift in hormones commonly seen during pregnancy, which results in patches of uneven pigmentation. Hormonal contraceptives and certain medications have also been linked to melasma. In some cases, once hormones have re-stabilized (for example post-pregnancy, or ceasing of hormonal medications) melasma is resolved. In other cases, the abnormal pigmentation persists.