19-30: Herpes Genitalis in Pregnancy

Infection of the lower genital tract by herpes simplex virus type 2 (HSV-2) (see also Chapter 6) is a common STD with potentially serious consequences to pregnant women and their newborn infants. Although up to 25% of women in an obstetric practice may have antibodies to HSV-2, a history of the infection is unreliable and the incidence of neonatal infection is low (10–60/100,000 live births). Most infected neonates are born to women with no history, symptoms, or signs of infection.

Women who have had primary herpes infection late in pregnancy are at high risk for shedding virus at delivery. Some experts suggest use of prophylactic acyclovir, 400 mg orally three times daily, to decrease the likelihood of active lesions at the time of labor and delivery.

Women with a history of recurrent genital herpes have a lower neonatal attack rate than women infected during the pregnancy, but they should still be monitored with clinical observation and culture of any suspicious lesions. Since asymptomatic viral shedding is not predictable by antepartum cultures, current recommendations do not include routine cultures in individuals with a history of herpes without active disease. However, when labor begins, vulvar and cervical inspection should be performed. Cesarean delivery is indicated at the time of labor if there are prodromal symptoms or active genital lesions.

For treatment, see Chapter 32. The use of acyclovir in pregnancy is acceptable, and prophylaxis starting at 36 weeks’ gestation has been shown to decrease the number of cesarean sections performed for active disease.