Mother-to-Infant Herpes Transmission
Cesarean Section and Other Steps Can Reduce Risk
Jan. 7, 2003 -- Women infected with herpes can reduce the risk of passing the virus on to their children by having a cesarean section and taking other safety precautions during pregnancy and delivery, according to a new study. Researchers say it's the first real proof that delivering a baby via cesarean section can protect an infant from infection with the herpes simplex virus (HSV), despite the fact that it's been common practice for the last 30 years.
The results of the study appear in the Jan. 8 issue of The Journal of the American Medical Association.
Researchers looked at 202 women who had HSV at the time of labor and gave birth at several hospitals in Washington State between 1982 and 1999. Of the infected women, 85 delivered by cesarean section and 117 delivered vaginally. Ten infants were infected with the virus.
But the researchers found that several factors appeared to reduce the risk of the mother passing the infection along to her child, and cesarean delivery was one of the biggest factors in preventing transmission. Only one baby who was delivered by C-section acquired HSV, compared with nine babies who tested positive for the virus after a vaginal delivery.
Study author Zane A. Brown, MD, of the University of Washington, and colleagues say women who had genital lesions at the time of labor were also less likely to transmit the virus to their infant, perhaps because these women were much more likely to have a cesarean delivery.
In fact, none of the 74 women who had lesions infected their infants, compared with 10 of the 128 women who were shedding the virus without lesions and infected their child.
Factors that increased the risk of transmission of the virus to the infant included the presence of HSV in the mother's cervix, the use of invasive monitoring devices during labor and delivery, and premature delivery (before 38 weeks). Mothers who were under the age of 21 or were experiencing their first episode of HSV infection were also more likely to pass the virus along to their child.
Symptoms of oral herpes include cold sores or fever blisters near the mouth, and genital herpes can cause lesions in the genital area.
The risk of acquiring either type of HSV can be reduced by using a latex condom during sex and avoiding sexual contact with visibly infected areas of the mouth and genitals. But a person infected with HSV-2, the form that generally causes genital herpes, may still be contagious even if they do not have visible symptoms.