The U.S. Food and Drug Administration is warning women of child-bearing age that the epilepsy drug Topamax can increase the risk of birth defects.

Data collected from a registry of pregnant women showed a higher rate of cleft lip and cleft palate in babies whose mothers were taking the drug during the first trimester.

Topamax is marketed by Johnson & Johnson to control seizures caused by epilepsy, a neurological disorder that causes excessive signals in the brain. The drug is also used to relieve migraine headaches.

J&J and generic drug makers who market the drug, known as topiramate, will add a stronger warning label about the drug's effect on a fetus, the FDA said Friday.

Women taking topiramate should talk to their doctor immediately if they are planning to or become pregnant.

Many of the products are sold in Canada. Health Canada has previously warned of rare reports, mainly in children, of decreased sweating and hyperthermia in patients treated with Topamax.