Melasma/Chloasma

Melasma "Mask Of Pregnancy" appears on the skin has a brownish patchy pigmentation on the face, Which is caused by overproduction of Melanin.

Causes.

Sun exposure – which is the most important avoidable risk
Pregnancy - If occurs in pregnancy is known to fade after several months. Melasma during pregnancy is relatively common. Sometimes it is called the "mask of pregnancy
Melasma - may be associated with hypothyroidism (low levels of thyroid hormone).
Soaps - Scented or deodorant soaps, toiletries and cosmetics can trigger Melasma.
Hormone treatments - oral contraceptive pills, this can affect a quarter of melasma sufferers, intrauterine devices and implants & hormone replacement can also be an important factor
A phototoxic reaction to certain medications may also trigger melasma.
Melasma is often associated with the female hormones estrogen and progesterone.
Deficiency of Folic Acid during pregnancy can also lead to development of Melasma.

Symptoms

Tan, dark brown patches, that form in an irregular shape. These patches usually develop on the upper cheek, upper lip and forehead. And fade over time, but there are no other symptoms other than cosmetic ones.

Treatment

Melasma usually dissapears after giving birth or stopping the contraceptive pill etc, treatments to hasten the darkend patches include:-

Hydroquinone (HQ) either in over-the-counter (2%) or prescription (4%) strength. Hq is an enzyme involved in the production of melanin.
Tretinoin - which is a acid, to help the skin turnover, whic can also be used in pregnancy.
Chemical Peels - getting rid over layers of skin, for severe damaged skin. Please see link for before & after pics. http://www.youtube.com/watch?v=RzBetCjbsfI