London, May 19 (IANS): A drug commonly used to treat pain, epilepsy, anxiety and other mental health disorders may be associated with an increased risk of major birth defects, a study warns.

The drug pregabalin is approved by the US Food and Drug Administration (FDA) to treat epilepsy, fibromyalgia and neuropathic pain, such as pain from diabetic neuropathy or pain after shingles or spinal cord injury.

It is also used for generalised anxiety disorder and other mental health issues.

"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 study author Ursula Winterfeld from Lausanne University Hospital in Lausanne, Switzerland.

For the study, information was collected in seven countries from 164 women who took pregabalin during a pregnancy and 656 pregnant women who were not taking any anti-seizure drugs.

The women or their practitioners were then contacted again after their expected date of delivery.

Pregnancies of the women who took pregabalin during the first trimester of pregnancy were three times more likely to result in major birth defects than those of the women who did not take anti-seizure drugs.

Seven of the 116 pregnancies in women taking anti-seizure drugs, or six percent, had major birth defects, compared to 12 of 580 pregnancies, or two percent, in women who did not take the drug.

The major birth defects included heart defects and structural problems with the central nervous system (CNS) or other organs.

Birth defects due to chromosomal abnormalities were not included in these results.

The study was published online in the journal Neurology.

"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,” Winterfeld said.

"In cases where women have taken pregabalin during pregnancy, extra fetal monitoring may be warranted," Winterfeld noted.