Anti-viral medicines can decrease Ceasarian sections for women who have herpes virus

(Adapted by ScienceDaily.com from materials provided by UT Southwestern Medical Center, via EurekAlert!, a service of AAAS.)

ScienceDaily (Jul. 10, 2006) — Administering anti-viral medication to pregnant women who have genital herpes significantly decreases the necessity of Caesarean sections—which are often needed to protect the infant from contracting the virus, a recent UT Southwestern Medical Center study found.

The UT Southwestern study, which appears in this month's issue of the journal Obstetrics and Gynecology, is the first large-scale proof that the drug valacyclovir hydrochloride (Valtrex) is effective in the final month of pregnancy.

"…this will help…in [providing] stronger evidence in using this treatment," said Dr. Jeanne Sheffield, who is the chief author of this study and assistant professor of obstetrics and gynecology at UT Southwestern. "[IN addition to] reducing…herpes outbreaks at birth…numbers of women without symptoms who were shedding the virus into the birth canal [were also deacresed]."

Herpes is characterized by an initial outbreak of genital sores, followed by months or years of inactivity and is recognized as one of the most common sexually transmitted infections. While it is incurable, the frequency and intensity of outbreaks can be decreased through use of proper medication. Due to periods of outbreak inactivity and lack of symptoms, many people, including women who are in the reproductive age, may not know they are infected with the herpes virus.

In some rare documented cases, infants have been found to contract the herpes simplex virus from the mother’s birth canal or genital area during birth, even when the mother is asymptomatic—or not currently experiencing an outbreak. Medical protocol for these instances is to recommend C-sections to women with active genital herpes lesions at the time of delivery. However, researchers found that 70 percent of neonatal herpes cases occur in newborns of women who shed the virus near delivery during a latent outbreak period.

"This study [attempted to] reduce … genital herpes lesions…to [prohibit] neonatal herpes," Dr. Sheffield said.

To conduct this study, The UT Southwestern research team used 338 pregnant women who had a history of genital herpes, in a randomized, double-blind trial—where both the doctors and women being studied were unaware of who was receiving medication.

Because of active herpes lesions, 28 of the women in this study underwent C-sections. Seven of the 170 women in the valacyclovir group (or 4 percent) had C-sections, while 21 of the 168 women in the placebo group (13 percent) had C-sections. The 69 percent decrease in the occurrence of the clinical herpes simplex virus at the time of birth was statistically noteworthy, the researchers reported.

No infants in either group contracted herpes at birth. Nor were there any variations in delivery complications between either group found in this study.

"This… [is] a well-designed study … to help [increase] confidence in the efficacy and safety of anti-viral suppression in late pregnancy," said Dr. George Wendel, professor of obstetrics and gynecology and senior research contributor.

In addition to Dr. Wendel, other UT Southwestern researchers who helped in facilitating this study were Dr. Vanessa Laibl, assistant professor of obstetrics and gynecology; Dr. Scott Roberts, associate professor of obstetrics and gynecology; and Dr. Pablo Sanchez, professor of pediatrics.

This research study was supported in part by GlaxoSmithKline.