28 year old pregnant female came to you with complaints of brownish pigmentation on the bridge of nose and cheek. She noticed it after returning from her vacation at beach. There is no pain or itching at the affected site. What is your most likely diagnosis?

This patient is pregnant and has noted the pigmentation after a period of exposure to the sun during her vacation, both these factors act as triggers for the development of chloasma. It is symmetrically seen on cheeks, nose, forehead and chin. Chemical peeling using glycolic acid and trichloroacetic acid is an impoant method of treatment. Medical treatment can be done using topical hydroquinone or azelaic acid. Ref: Illustrated Synopsis of Dermatology and Sexually Transmitted Diseases By Neena Khanna 2ND edn page 135.