Acyclovir prophylaxis in late pregnancy prevents recurrent genital herpes and viral shedding

Neonatal herpes affects about 1 in 15,000 newborns and the prognosis for di sseminated disease with encephalitis is poor. We investigated whether acycl ovir prophylaxis in late pregnancy effectively reduces the risk of viral sh edding and. hence, of mother-to-child transmission at delivery. A prospective study was conducted. Pregnant women who had at least one epis ode of genital herpes during pregnancy were randomly assigned to two groups : group 1 (n=167) received oral acyclovir from 36 weeks of gestation to ter m, group 2 (n=121) received no treatment. Group 3 (n=201) comprised women n ot given prophylaxis who had a history of genital herpes. but no active epi sodes during pregnancy. No specific instruction were set up for obstetrical management except For cesarean section in case of a suspected herpes lesio n at the time of labor. The rate of Cesarean section was 8.3% in group 1, 16.54 in group 3, and 9.9 % in group 3 (p<0.001). 75% of cesareans in group 2 and 10% in group 3 were done for genital herpes. Percentage of viral shedding was, respectively. 0 % (group 1), 5% (group 2), and 0.5% (group 3) (p<0.05). These findings underline the value of antiviral prophylaxis in late pregnan cy for women with a known history of genital herpes. Such prophylaxis only partly prevents neonatal herpes infection, because it is not applicable: to patients with no known clinical history but may excrete the virus. (C) 200 1 Elsevier Science Ireland Ltd. All rights reserved.