A call has been
made for better communication between women with epilepsy and their
doctors, as well as more research into the effects of anti-epileptic
drugs (AEDs) on unborn children.
Experts, convened by the International Bureau for Epilepsy,
have revealed that some epilepsy pregnancy registers have yielded
conclusive results on the risks of serious birth defects associated
with some commonly used AEDs, and it is vital, the Bureaus says, that
women of childbearing potential understand these risks and what they
can do to minimise them.
the general population, the risk of serious birth defects is between
two and three per cent. However, statistically significant results have
been recently announced for two major AED registers, the UK Epilepsy and Pregnancy Register and the North American Antiepileptic Drug Pregnancy Register.
UK register, which tracked 2,637 pregnant women taking AED monotherapy
(single-drug therapy), found that lamotrigine and carbamazepine had a
significantly lower birth defect incidence (2.1 per cent and 2.3 per
cent, respectively) compared to valproic acid (5.9 per cent).
North American register, including more than 3,400 women, found major
birth defects in 7.3 per cent of babies exposed to valproate compared
with 2.8 per cent in other monotherapies.
addition, preliminary results of an Australian register of 565
pregnancies found that 19 babies with major malformations were born to
116 women on valproate monotherapy (16 per cent). Carbamazepine
monotherapy yielded five birth defects out of 159 pregnancies (3.1 per
cent); phenytoin monotherapy, one out of 18 (5.6 per cent); and
lamotrigine monotherapy, zero out of 63 (zero per cent).
Diego Wyszynski, senior epidemiologist with the North American Antiepileptic Drug Pregnancy Registry, said:
preliminary but very informative results clearly show that not all AEDs
are equally safe for the exposed children of pregnant women of
childbearing potential. Physicians can now have greater confidence in
their ability to treat women with epilepsy of childbearing potential
while minimising any risks to the unborn child.
50 per cent of women with epilepsy continue using the first AED ever
prescribed to them. Therefore, whenever possible, physicians who treat
girls and young women with this condition should consider offering only
those drugs that pose the smallest risk of birth defects."