Changes in the frequency of genital herpes recurrences as a function of time.

To obtain objective information regarding changes in the frequency of recurrent genital Herpes simplex infections, the data from two consecutive pregnancies in 22 women with culture-proved genital Herpes simplex infections were reviewed. The pregnancies studied were separated by a mean of 2.0 years. When only culture-proved recurrences were considered, nine women had fewer recurrences in their second pregnancy than in their first, four had more recurrences in their second than in their first, and nine had the same number of recurrences in both pregnancies. The mean interval between culture-proved recurrences was 58.5 +/- 36.1 (SD) days in first pregnancies and 51.7 +/- 28.6 days in second pregnancies. Mean duration of viral shedding during 14 recurrences in first pregnancies was 4.6 +/- 3.4 days, and 3.2 +/- 2.2 days in 14 recurrences in second pregnancies (differences not significant by Mann-Whitney). Cervical Herpes simplex shedding in asymptomatic women occurred in four of 200 (2.0%) of first pregnancy cultures and zero of 167 second pregnancy cultures (NS). During culture-positive recurrent vulvar infections, 18 of 55 (32.7%) cervical cultures in first pregnancies were positive compared with four of 50 (8%) cervical cultures in second pregnancies (P less than .025). Route of delivery was very similar in the first and second pregnancies with vaginal delivery in 63.6% of first pregnancies and 72.7% of second pregnancies. Overall there was no appreciable difference in the frequency or severity of recurrent genital Herpes simplex infections over time, but more data are needed.