A new study has revealed that the drug pregabalin - brand name Lyrica - might be associated with an increased risk of major birth defects. Commonly used to treat pain, epilepsy and various other neurological disorders, the FDA-approved drug is also prescribed off-label for generalized anxiety disorder and mental health issues.

The researchers examined 164 women across seven countries who took pregabalin during pregnancy, as well as 656 pregnant women who were not taking any kind of anti-seizure drugs. After their expected date of delivery, they were contacted again for further information.

The results revealed that women who took pregabalin during the first trimester of pregnancy were three times more likely to experience pregnancies with major birth defects in comparison to the women who did not take anti-seizure drugs. Overall, six percent of the women taking anti-seizure drugs had major birth defects, while just two percent of those who did not take these drugs had birth defects.

Major birth defects encompass heart defects and central nervous system (CNS) structural problems. In regards to CNS problems, 3.2 percent of the women in the study taking pregabalin experienced them, compared to just 0.5 percent in women who did not take the drug.

Of the women in the study, 77 percent of them began taking Lyrica prior to pregnancy, and they stopped taking the drug at an average of six weeks into their pregnancies. Furthermore, of those on the medication, 13 percent were taking an additional anti-seizure drug.

"We can't draw any definitive conclusions from this study, since many of the women were taking other drugs that could have played a role in the birth defects and because the study was small and the results need to be confirmed with larger studies, but these results do signal that there may be an increased risk for major birth defects after taking pregabalin during the first trimester of pregnancy," said Ursula Winterfeld of the Swiss Teratogen Information Service and lead author of the study.

"Pregabalin should be prescribed for women of child-bearing age only after making sure that the benefits of the drug outweigh the risks and after counseling them about using effective birth control," she added. "In cases where women have taken pregabalin during pregnancy, extra fetal monitoring may be warranted."

The findings were published online in the May 18 issue of the journal Neurology.