Chloasma is a common skin condition that occur during hormonal changes in pregnancy or during use of oral contraceptive pill. The condition causes tan to gray-brown patches on the face and develops mainly on the face. It affects women of all ethnic groups, but particularly those with Fitzpatrick skin types III–VI . It is also known as chloasma or mask of pregnancy.

Chloasma usually forms on the cheeks, bridge of the nose, forehead, chin, and upper lip, and occasionally on the forearms and neck. It may develop during or after pregnancy, while taking birth control pills or during menopause. Sometimes it appears for no obvious reason.

It is more common in people that tan well or have naturally dark skin compared with those who have fair skin, particularly if they live in a sunny area. It is often seen in Asia, the Middle East, South America, Africa and the Indian subcontinent. Tan or brown spots are seen mainly on the cheeks, jaw, forehead, nose, chin, and above the upper lip.

Chloasma is sometimes separated into epidermal (skin surface), dermal (deeper) and mixed types. The dermal and mixed types are significantly more difficult to treat than the superficial form of pregnancy masks. The type of chloasma can be diagnosed clinically with the help of a Wood’s Lamp or a skin biopsy may be necessary to determine the depth of the disorder.

Type of Chloasma

Superficial Mask

• Well-defined border

• Dark brown colour

• Appears more obvious under Wood’s Lamp

• Responds well to treatment

Deep Mask

• Ill-defined border

• Light brown or brown-grey colour

• Unchanged under Wood’s Lamp

• Responds poorly to treatment

Mixed Mask

• Combination of light and brown patches

• Partial improvement with treatment