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What is Acquired symmetric hyper pigmentation of the sun exposed skin of the face and neck, which is strongly associated with pregnancy & use of oral contraceptives is called- and explain in detail?
(Ref: Burket, Ed. 10th Pg-132) * Melasma or Cholasma describes the discrete patches of facial pigmentation which occur in pregnancy and in some women taking oral contraceptives. * This pigmentation is seen paicularly in periorbital and perioral region.