Pregabalin may be associated with an increased risk of major birth defects, according to a study published in the May 18, 2016, journal Neurology.
The drug is approved by the US Food and Drug Administration (FDA) to treat epilepsy, fibromyalgia, and neuropathic pain. It is also used for generalised anxiety disorder and other mental health issues.
For the current study, information was collected in 7 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 3 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 (6%) had major birth defects, compared with 12 of 580 pregnancies (2%) in women who did not take the drug. Birth defects due to chromosomal abnormalities were not included in these results.
The major birth defects included heart defects and structural problems with the central nervous system (CNS) or other organs.
The women taking pregabalin were 6 times more likely to have a pregnancy with a major defect in the CNS than women who were not taking the drug, with 4 CNS defects out of 125 pregnancies (3.2%), compared with 3 CNS defects out of 570 pregnancies (0.5%).
Of the women taking pregabalin, 115 were taking it to treat neuropathic pain, 39 were taking it for psychiatric disorders, including depression, anxiety, bipolar disorder and psychosis, 5 were taking it for epilepsy, and 1 was taking it for restless leg syndrome.
A total of 77% of the women started taking pregabalin before they became pregnant. The women in the study stopped taking the drug at an average of 6 weeks into their pregnancies. Of the women taking pregabalin, 22 (13%) were also taking another 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, PhD, Swiss Teratogen Information Service and Lausanne University Hospital, Lausanne, Switzerland.
“Pregabalin should be prescribed for women of child-bearing age only after making sure that the benefits of the drug outweighs the risks and after counselling them about using effective birth control. In cases where women have taken pregabalin during pregnancy, extra fetal monitoring may be warranted,” she added.