Ans- D Erythematous urticarial patches and plaques (classically periumbilical) that progress to tense vesicles and blisters in a pregnant woman is herpes gestationis (also known as pemphigoid gestationis). There is no association to the husband's URI. Herpes gestationis is a pruritic blistering dermatologic disorder unique to pregnancy. It is not associated with past or present herpes infection. The onset is generally later in pregnancy (second trimester or later). The distribution involves the abdomen or extremities but may be generalized. It is thought to be an autoimmune condition triggered by pregnancy, with antibodies against hemidesmosomal proteins. It is associated with other autoimmune diseases such as Hashimoto's thyroiditis, Grave's disease, or pernicious anemia. Tunzi et al. describe some of the major pregnancy-specific skin conditions, which include pruritic urticarial papules and plaques of pregnancy, prurigo of pregnancy, intrahepatic cholestasis of pregnancy, pemphigoid gestationis, impetigo herpetiformis, and pruritic folliculitis of pregnancy. The majority of skin conditions resolve postpartum and require only symptomatic treatment. Lipozencic et al. detail the specifics of diagnosing pemphigoid gestationis, which includes the presence of subepidermal vesicles on routine histologic examination and the linear deposition of C3 and IgG along the basement membrane of perilesional skin. Detection of C3 and IgG is accomplished by immunofluorescence microscopy. Figure A displays the classic findings of vesicular skin lesions in a pregnant woman with herpes gestationis. Illustration A displays herpes zoster, note the dermatomal distribution. Illustration B displays bullous pemphigoid. Illustration C displays pruritic urticarial papules and plaques of pregnancy. Incorrect Answers: Answer 1: Herpes zoster is a viral skin condition affecting only one dermatome. Answer 3: Intrahepatic cholestasis of pregnancy involves diffuse burning and itching without visible skin changes. Answer 2: Pruritic urticarial papules and plaques of pregnancy presents with umbilical-sparing abdominal skin wheals.