Maternal Acyclovir.

Pregnant women with herpes simplex lesions usually undergo cesarean section to prevent the newborn from acquiring herpes infection (with its serious repercussions) during passage through the vagina at birth. A decision analysis compares this expensive approach with other strategies for mothers with recurrent genital herpes: acyclovir prophylaxis in late pregnancy, followed by C-section if lesions are present at delivery; acyclovir prophylaxis and vaginal delivery, with culture and treatment of the newborn; or no intervention.

Based on assumptions derived from published studies, performing C-sections on all women with genital herpes at delivery was estimated to prevent 2.8 cases of neonatal herpes and lead to 1082 C-sections per 10,000 women with recurrent genital herpes. Acyclovir prophylaxis plus C-sections for women with lesions would prevent 5.5 cases and lead to 216 C-sections per 10,000. Prophylaxis with vaginal delivery and infant culture would prevent 5 cases; and no intervention would result in 6.2 to 7.6 neonatal herpes cases.

The conclusion was that acyclovir treatment of genital herpes in late pregnancy not only prevents more neonatal herpes cases than cesarean section without treatment, it is also cost-effective. Acyclovir plus C-section in cases of active lesions was deemed by the journal to be optimal therapy. (That is, they concluded that it was worth 216 cesarean sections to prevent 0.5 cases of neonatal herpes per 10,000 women with recurrent genital herpes.)

Since acyclovir has not been approved by the FDA for use in pregnancy, patients offered acyclovir should be informed that, while few data exist, it does not seem to be harmful based on anecdotal evidence.

--Journal Watch: Women's Health, 12/96