Prescribing in pregnancy. Epilepsy and anticonvulsant drugs.

An epileptic seizure is a paroxysmal discharge of cerebral neurones resulting in a clinical event apparent to the subject or an observer, or both. Tonic-clonic (grand mal) seizures are common and most disruptive of fife, but many patients have combinations of complex partial (temporal lobe) seizures and tonic-clonic seizures. Epilepsy, which is best defined as a continuing tendency to epileptic seizures, affects about 0*5% of women of childbearing age.1 Thus family doctors and obstetric units will from time to time have a pregnant woman with epilepsy under their care. A unit delivering 3000 mothers a year will have about 15 pregnant women with epilepsy on their books at any one time. It must be remembered that seizures, particularly if they occur in the third trimester, may be due to eclampsia rather than epilepsy. Although modern antenatal care makes it unlikely that eclamptic seizures will occur without previous evidence of pre-eclampsia, many patients presenting with eclampsia have not attended for antenatal care. Furthermore, eclampsia may appear suddenly, particularly during or after delivery. Epilepsy and oral contraception