Epilepsy Action Annual Research Prize 2004 - Dr James Morrow

The UK Epilepsy and Pregnancy Register: Prospective monitoring of anti-epileptic drugs used during pregnancy 1996-2003

Dr James Morrow

Consultant Neurologist, The Royal Hospitals Belfast

Anti-epileptic drugs (AEDs) taken during pregnancy are associated with an increased risk of malformations in children. The absolute risk for each of the individual AEDs and their relative risks in terms of frequency and type of malformation have been difficult to define from earlier studies. The emergence of a number of newer AEDs in the last decade, for which there is little of no human safety data in pregnancy, has further compounded the difficulties faced by the physician attempting to offer pre-conception advice to women with epilepsy.

The UK Epilepsy and Pregnancy Register is a prospective, observational registration and follow up study. Women with epilepsy who become pregnant, whether on no AED, a single AED or any combination of AEDs are registered early in the course of their pregnancy, before outcome is known, from a broad professional base and by self registration. Follow up information is collected from patient’s General Practitioner 3 months after the expected date of delivery.

Full outcome data has been collected from 2967 cases. The vast majority of women were taking a single drug. The most commonly prescribed drugs were Carbamazepine (Tegretol), Sodium Valproate (Epilim) or Lamotrigine (Lamictal).

The results indicate that over 95 per cent of all pregnancies in women with epilepsy do NOT result in a child with a major congenital malformation. Monotherapy, i.e. treatment with a single drug, carries less risk than polytherapy. Some treatment groups do appear to be at higher risk; particular those women taking Na Valproate both in Monotherapy or as part of a polytherapy regime. However, even in these cases the absolute risk remains low.