Pregnancy outcome in patients with pityriasis rosea

The effect of pityriasis rosea (PR) on the outcome of pregnancy has not been previously reported.

We sought to investigate the possible impact of PR in pregnant women.

In all, 38 women who developed PR during pregnancy were observed. In one of them, who developed PR at 10 weeks' gestation and aborted 2 weeks later, plasma, peripheral blood mononuclear cells, maternal skin, and placental and embryonic tissues were studied by quantitative calibrated real-time polymerase chain reaction for human herpesviruses (HHV)-6 and -7. Controls included plasma from 36 healthy blood donors, plasma and paraffin-embedded tissue sections from 12 patients with other dermatitides, and from placental and embryonic tissues from one woman who presented with a 19-week intrauterine fetal death.

Of the 38 women, 9 had a premature delivery and 5 miscarried. In particular, 62% of the women who developed PR within 15 weeks' gestation aborted. Neonatal hypotonia, weak motility, and hyporeactivity were noted in 6 cases. In the patient studied in detail, HHV-6 DNA was detected in plasma, peripheral blood mononuclear cells, skin, and placenta and embryonic tissues, whereas HHV-7 DNA was absent. HHV-6 p41 antigen was detected by immunohistochemistry in skin lesions, placenta, and embryonic tissues. No herpesvirus DNA was detected in plasma and tissues from control subjects.

This is a case series study with a small number of patients.

PR may be associated with an active HHV-6 infection. In pregnancy, PR may foreshadow premature delivery with neonatal hypotonia and even fetal demise especially if it develops within 15 weeks' gestation.