Melasma is a common skin condition where patches of skin become darker than the surrounding area. It presents as brown or grayish-brown patches, typically on the face. This darkening is a form of hyperpigmentation, which simply means there's an overproduction of melanin, the natural pigment that gives color to our skin, hair, and eyes.

The patches are usually well-defined with an irregular border, appearing like a blotchy map on the skin. They are completely flat, not raised, and don't cause any physical discomfort like itching or pain. Because of its common appearance during pregnancy, melasma is often nicknamed the "mask of pregnancy," although it can affect anyone.

While anyone can develop melasma, it's far more common in women than in men. In fact, reports suggest that women account for about 90% of cases. The condition is most likely to appear during the reproductive years, typically between the ages of 20 and 40.

Skin tone is another significant factor. People with darker skin types are more prone to developing melasma because their pigment-producing cells, called melanocytes, are more active. A family history of the condition also increases your chances of getting it, suggesting a genetic predisposition.

Melasma almost always appears on parts of the body that get a lot of sun exposure. The face is the most common site by far.

Less frequently, melasma can develop on other sun-exposed areas like the forearms and neck. It's very rare to see it on other parts of the body.