The MHRA has advised UK health professionals to note a new study highlighting the increased risk of major congenital malformations associated with taking pregabalin while pregnant. 

The observational study of more than 2,700 pregnancies in which pregabalin was taken during pregnancy found the drug poses a “slightly” increased risk of malformations of the nervous system, eye, face, urinary system and genitals.

The study, which used data from Denmark, Finland, Norway and Sweden from the 10 years up to 2015-16, also found that the proportion of pregnant women using the drug rose during this period.

The data indicates the risk of major congenital malformations is “slightly higher” when pregabalin is taken in pregnancy than in the baseline population or where alternative therapies lamotrigine or duloxetine are taken. 

The rate of malformations was 5.9 per cent in the pregabalin group compared to 4.1 per cent of pregnancies in which there was no exposure to pregabalin or other antiepileptic drugs.

However, estimates may be “imprecise” due to the low number of overall cases, said the MHRA.

The study data appears to support the MHRA’s advice update from January 2021 in which it said that pregabalin should be avoided during pregnancy “unless clearly necessary and only if the benefit to the patient clearly outweighs the potential risk to the fetus,” and that patients should have a “full understanding” of the potential benefits and risks, as well as the alternative therapies available.

In cases where the benefit outweighs the risk and pregabalin should “clearly” be used during pregnancy, the MHRA advises prescribers to use the lowest effective dose and report any suspected adverse reactions – including for the baby – using the Yellow Card Scheme.