Papular dermatitis of pregnancy.

Papular dermatitis of pregnancy is a rare pruritic eruption of widespread urticarialike papules. The eruption developed in a 31-year-old woman during the third trimester of her second pregnancy. Urine chorionic gonadotropin (UCG) levels were elevated. A biopsy specimen of an involved papule showed spongiosis and a perivascular lymphocytic infiltrate in the superficial dermis. No deposits of IgG, IgM, IgA, or C3 were detected by direct immunofluorescence microscopy of perilesional skin. High doses of systemically administered corticosteroids controlled the disease, but papules developed in increased numbers when the dosage was reduced below 80 mg/day. After parturition, widely scattered papules of similar morphology developed in the patient; these persisted for 11 months despite the absence of retained placental fragments and normal findings from UCG determinations. New papules continued to develop premenstrually, suggesting an influence of normal pituitary gonadotropic hormones or other aggravating humoral factors on the eruption.