PREGABALIN is an effective drug used in treating painful neuropathic conditions, anxiety disorders and is also adjunct therapy for partial seizure disorders. It’s safety in pregnancy is under FDA Category C – which means that animal studies suggest adverse fetal outcomes but no controlled human studies have been done. As such, when considering its use during pregnancy, the physician should weigh maternal benefit against fetal risk.
But recently, a multicenter observational cohort suggests that pregabalin exposure (particularly during the first trimester) was associated with a three-fold increased risk for major birth defects – with risks being higher for central nervous system malformations.
The risk of major birth defects in the PGB exposed group was 6% versus 2.1% in the control group (odds ratio 3). The odds ratio did not seem to be affected after controlling for treatment with anti epileptics, benzodiazepines, antidepressant, alcohol and twin pregnancies. CNS malformations were also higher at 3.2% (vs. 0.55% in controls).
Unfortunately, the cohort study consisting of 164 pregabalin exposed pregnancies versus 656 controls (reviewed by the Tetralogy Information Services; with data obtained from France, UK, Italy, Finland, Netherlands, Turkey and Switzerland) had several limitations. First, of which, was the relatively small sample size. Furthermore, there were several other confounders which significantly differed between groups – concurrent medications (and other co morbid illnesses), AOG at contact (earlier in PGB group), tobacco use (higher again in the PGB group), unplanned pregnancies (also higher in the PGB group) and history of prior spontaneous abortions (more in the PGB group too).
The authors admit that the study DOESN’T establish an increased risk with pregabalin but rather alerts regulators to the possibility and suggests that further confirmation through better trials are needed.
The team advises that prescription of pregabalin in women of child bearing age should be made only for valid indications and after due assessment of the risks and benefits. Enhanced fetal monitoring may be warranted for patients exposed to pregabalin during pregnancy.
Reference: Winterfeld U, et al. Pregnancy Outcome following maternal exposure to pregabalin may call for concern. Neurology 2016. doi: http://dx.doi.org/10.1212/WNL.0000000000002767