Acquired skin disease with symmetrical facial over-coloring mainly in women of reproductive age and more often in dark skins. Caused by hormonal disorders (pregnancy, contraceptives, thyroid) and exposure to ultraviolet radiation. There is usually a family history. Histologically, the melasma has an increased presence of melanin in all layers of the skin. Treatments, although there are many (lasers, peelings, whitening creams), usually do not completely recover and recur very easily.