Despite the fact that gabapentin (Neurontin) is now used in a wide variety of clinical settings — for epilepsy, pain management, anxiety, sleep disturbance – there is relatively little information regarding its reproductive safety. A prospective study from researchers at the Motherisk program reports on the outcomes of 223 pregnancies exposed to gabapentin and 223 unexposed pregnancies.
The rates of major malformations were similar in the two groups. There was a higher rate of preterm births and low birth weight (less than 2,500 g) in the gabapentin group. Among infants who were exposed to gabapentin up until delivery, 23 of 61 (38%) were admitted to either the neonatal intensive care unit or special care nursery for observation and/or treatment, versus only 6 of the 201 (2.9%) infants in the comparison group. Among the women taking gabapentin, the major indications were pain (n=90; 43%) and epilepsy (n=71; 34%); the remainder took gabapentin for other indications, mostly psychiatric.
This report is consistent with other reports on the reproductive safety of gabapentin. A recent study included 59 infants exposed to gabapentin; one (1.7%) was noted to have a major malformation. Although in this study more exposed versus non-exposed infants were preterm, low birthweight, or were admitted to the special care nursery for observation, it is not possible to determine if these outcomes were caused by exposure to the medication or were related to other factors (such as the underlying illness).
All in all, the data are reassuring; however, it should be noted that they are still rather small in size. It is estimated that at least 400 to 600 exposures would be required to detect a 2-fold increase in more common malformations. Further research is essential to better clarify the reproductive safety of this medication.
Ruta Nonacs, MD PhD
Fujii H, et al. Pregnancy outcomes following gabapentin use: Results of a prospective comparative cohort study. Neurology. 2013 April 3.