According to a report published in, Journal of the American Medical Association, certain antiviral medications during early pregnancy may not increase the child’s risk of major birth defects. Antiviral medications including acyclovir, valacyclovir, and famciclovir, are often prescribed for the treatment of herpes viral infections. According to the report, more than one in five women has HSV antibodies, which indicate past or present infections.
Herpes antiviral medications are also used to treat herpes zoster infections called shingles. The report mentions that information regarding the safety of herpes antiviral medications during pregnancy was very limited till now. The number of safety studies on pregnant women was less, and hence FDA had classified these drugs under category B.
The present study clearly shows that pregnant women can take these medications without any birth defects to the baby. In this study, the researchers analyzed the data from 800,000 infants born between January 1996 and September 2008. They analysed the association between the use of antiviral drugs like acyclovir, valacyclovir, and famciclovir during the first trimester of pregnancy and birth defects in babies. None of the participants had a medical history of chromosome or genetic problems or viral infections at birth. All other factors that are known to influence the outcome of the result was adjusted for.
The study authors report that the study is the largest of its kind and no significant association was found between the use of antiviral drugs during the first trimester and major birth defects. Acyclovir was the most common antiviral used and hence can be considered as the drug of choice in early pregnancy.
Analysis of famciclovir was based on data from few pregnant women and hence should not be viewed as evidence of safety of this drug. Data on valacyclovir also is insufficient, they add.
- Certain antiviral medications during early pregnancy may not increase the child’s risk of major birth defects.