Comparison of Neonatal HSV Risk Factors in Cesarean and Vaginal Deliveries

Background:
Neonatal herpes (NNH) is a potentially devastating infection caused by herpes simplex virus type 1 or type 2 (HSV-2). CDC guidelines recommend that pregnant women be asked about history of genital herpes and examined for herpetic lesions at onset of labor. The majority of specialists recommend women with genital lesions at onset of labor deliver by cesarean section to prevent NNH.

Objective:
To determine the prevalence of maternal history of genital herpes and genital lesions in cesarean as compared to vaginal deliveries.

Method:
As part of a study of NNH incidence, information on maternal history and herpetic lesions was gathered from medical chart abstractions of infants born from 1997-2002 who received a diagnosis of potential NNH or NNH compatible disease. The study was conducted at three HMO's participating in the Vaccine Safety Datalink project; 90% of births occurred in two HMOs located on the West Coast.

Result:
A total of 746 infants were included in this analysis; mean maternal age was 28 years. Maternal history of genital herpes was noted in the chart of 15 (4%) of 378 infants delivered by cesarean section, and 19 (5%) of 369 infants delivered vaginally (p=0.4). Two women were known to be HSV-2 seropositive; neither had genital lesions at delivery, and one had a cesarean section. Of ten women who had genital lesions at delivery, 5 (50%) had cesarean sections.

Conclusion:
Among infants with potential NNH or NNH compatible disease who were delivered by cesarean section, percentages of mothers with a history of genital herpes or known HSV-2 serostatus were low and comparable to those who had vaginal deliveries. Among women with genital lesions at delivery, half delivered by cesarean section.

Implications:
Reasons for the low rate of cesarean deliveries among those with genital lesions should be further explored.