Pruritic Urticarial Papules and Plaques of Pregnancy 

The term pruritic urticarial papules and plaques of pregnancy (PUPPP) refers to a benign dermatosis that usually arises late in the third trimester of a first pregnancy.^[1] The entity previously had been reported as toxemic rash of pregnancy,^[2] toxemic erythema of pregnancy, and late-onset prurigo of pregnancy. The term polymorphic eruption of pregnancy is used extensively in Europe, while PUPPP typically is used in the United States. (See Presentation.)

Following atopic eruption of pregnancy, which occurs earlier in gestation, PUPPP is the second most common dermatosis of pregnancy. (See DDx.)^[3] One European author proposes that early gestational papular dermatoses (usually atopic eruption of pregnancy) be referred to as "early-onset PEP," distinguished from "late-onset PEP" (classic PUPPP).^[4]

PUPPP occurs in 1 out of 160 pregnancies. The condition may be less common in blacks.

Patient education

The patient should understand that PUPPP is a benign disorder and has not been shown to have adverse consequences for the fetus. Fully explain the side effects of corticosteroids and antihistamines (which are used in the treatment of PUPPP). Reassure the affected patient that PUPPP does not usually recur with subsequent pregnancies and will not be triggered by future use of oral contraceptives. (See Prognosis, Treatment, and Medication.)

The cause and pathogenesis of pruritic urticarial papules and plaques of pregnancy (PUPPP) are not known. A meta-analysis revealed that 11.7% of patients with PUPPP had multiple gestation pregnancies.^[5] Within that group, a higher PUPPP risk for triplet (14%) over twin (2.9%) pregnancies was found,^[6] suggesting a relationship between skin distention and the development of PUPPP. Most studies have revealed increased maternal weight gain in patients with PUPPP when compared with normal pregnancies, further supporting the role of increased skin distention.^[7]

A study from Israel also found maternal hypertension and induction of labor to be significantly associated with the condition.^[8] One large series^[9] of cases revealed a male-to-female infant ratio of 2:1.

Investigators identified fetal deoxyribonucleic acid (DNA) in the skin of mothers with PUPPP, suggesting that chimerism may be relevant to the pathogenesis of this disorder.^[10] Finally, a case-control study from France confirmed previously documented associations with multiple gestations, cesarean deliveries, and male fetuses, although no relationship to maternal or fetal weight gain was noted.^[11]

The prognoses for the affected woman and her newborn are excellent in pruritic urticarial papules and plaques of pregnancy (PUPPP). PUPPP typically resolves within 4-6 weeks, independent of delivery,^[7] and the condition does not tend to recur in subsequent pregnancies. Only 7% of multiparous PUPPP patients described a similar rash with prior pregnancies.^[3] Patients who have had PUPPP cannot precipitate a return of the condition through the subsequent use of oral contraceptives.

No mortality is associated with PUPPP. The mere appearance of an unusual skin eruption in pregnancy can provoke anxiety, but the pruritus is the most distressing feature. The latter weeks of pregnancy can be associated with many physical symptoms, and the severe itching of PUPPP may further debilitate and aggravate sleep loss in the weeks prior to delivery. No known systemic complications exist for affected females, and fetal mortality or morbidity do not increase.