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
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
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
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
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.