Approximately 1 million women of childbearing age in the United States have seizure disorders. Of these women, approximately 24,000 give birth each year.
Concerns during these pregnancies include the risk of fetal malformation, miscarriage, perinatal death, and increased seizure frequency.
In women who are pregnant, the volume of distribution and the hepatic metabolism of antiepileptic drugs (AEDs) are increased. This, along with decreased compliance with AEDs because of concerns about their effects on the fetus, leads to an increase in seizure frequency, which is observed in as many as 17-33% of pregnancies.
The use of AEDs is associated with a greater baseline risk of fetal malformations during pregnancy. When treating pregnant women who have epilepsy, the risks of increased seizure frequency versus the risks of AED use must be weighed carefully.
A population-based study conducted in Norway found that pregnant women with epilepsy had a lower risk of complications but an increased risk of induction, cesarean delivery, and postpartum hemorrhage.
However, whether this is a result of AEDs or severe epilepsy is unclear.
Go to Women’s Health and Epilepsy for complete information on this topic.
Epilepsy management before and after conception
Preconceptual management of women with epilepsy includes the following:
Attempt to decrease pharmacotherapy to monotherapy
Taper dosages of AEDs to the lowest possible dose
In women who have not had a seizure for 2-5 years, attempt complete withdrawal of pharmacotherapy
Establish the level of total and free AEDs necessary for achieving good clinical control
Consider preconceptual genetic counseling
Supplement the diet with folate at 4 mg/d
Management of women with epilepsy during pregnancy includes the following:
Check total and free levels of AEDs monthly
Consider early genetic counseling
Check maternal serum alpha-fetoprotein (MSAFP) levels and perform a level II fetal survey and ultrasonography at 19-20 weeks’ gestation
Consider amniocentesis for alpha-fetoprotein and acetylcholinesterase
Management of women with epilepsy upon labor and delivery includes the following:
Check levels of AEDs
Inform all care providers, including nurses, anesthesiologists, and pediatricians that the patient has epilepsy
Consider seizure prophylaxis with intravenous benzodiazepines or phenytoin
Manage seizures acutely with intravenous benzodiazepines (1-2 mg of diazepam), then load phenytoin (1 g loaded over 1 h)
Labor management should be based on routine standards of care
Start administration of vitamin K for the infant, and send the cord blood for clotting studies
Management of a pregnant patient in status epilepticus includes the following:
Establish the ABCs, and check vital signs, including oxygenation
Assess the fetal heart rate or fetal status
Rule out eclampsia
Administer a bolus of lorazepam (0.1 mg/kg, ie, 5-10 mg) at a rate of no more than 2 mg/min
Load phenytoin (20 mg/kg, ie, 1-2 g) at a rate of no more than 50 mg/min, with cardiac monitoring.
If this is not successful, load phenobarbital (20 mg/kg, ie, 1-2 g) at a rate of no more than 100 mg/min.
Check laboratory findings, including electrolytes, AED levels, glucose, and toxicology screen.
If fetal testing results are nonreassuring, move to emergent delivery
For more information, see Epilepsy and Seizures.