Understanding Antiepileptic Drug Use and Pregnancy

Antiepileptic Drugs

Antiepileptic drugs (AEDs) used to control seizures in people with epilepsy, are also becoming more commonly prescribed for the treatment of non-epileptic neurological pain symptoms such as migraines and tremor, and for psychiatric disorders such as mood and bipolar disorders. During the 12-month period ending September 2004, more than 56 million prescriptions for AEDs were written in the United States.¹ The development and availability of newer-generation AEDs has broadened the number of therapeutic options available to patients. There is evidence to suggest that newer AEDs have a more favorable tolerability and drug interaction profile compared to their older counterparts.²

AEDs and Pregnancy

Studies show that there may be an increased risk to babies born to women who have taken or are taking AEDs.³ In the general population, there is a two to three percent chance that a child will be born with a major congenital malformation, as defined by the Centers for Disease Control and Prevention.⁴ In contrast, for babies born to women being treated with an AED, this risk is sometimes increased to between four and eight percent.³

• Possibility of Birth Defects: Examples of birth defects found in babies born to women who have taken AEDs include cleft lips or palates (portions of the mouth do not grow together properly), heart abnormalities and neurological problems such as spina bifida (deformities of the spinal cord). Wide-set eyes, short upper lip or slight differences in the shape of the fingers and nails are other common malformations found in these babies.⁵
  
  
  
• Effect on Contraceptives: Some AEDs also can reduce the effect of hormonal contraceptives, thereby increasing a woman's chance of becoming pregnant unintentionally. Given that 50 percent of pregnancies are unplanned, data suggests that women in their reproductive years need to think more about their drug treatments.⁶
  
  
• Preventative Care: Women taking AEDs are strongly encouraged to:
  • Talk with their physician about AED risks and treatment options that may lower the risk of birth defects in advance of pregnancy;
  • Take the fewest number of drugs possible to control seizures, as multiple AED therapy has been associated with an increased rate of birth defects;
  • Routinely monitor AED blood levels and alter doses as may be appropriate;
  • Take folic acid because it may play a part in reducing the risk of birth defects;
  • Stay on top of emerging information and data about AEDs;
  • If pregnant, enroll early on in a pregnancy registry to add to the body of knowledge and help other mothers and babies;
  • Do not reduce or discontinue medication without advice from a doctor, as seizures could do more harm to the unborn child than AEDs; and
  • Consult a doctor to find the medication that works best for them— i.e., balances seizure risk against birth-defect risk.

1 Scott-Levin's NRx Monthly AED market report.

2 Spina1, Edoardo and Perugi, Giulio. "Antiepileptic drugs: indications other than epilepsy." Epileptic Disord. 2004;6: 57-75.

3 French, Jacqueline, "Ask the Expert: Pregnancy," 20 May 2004, Epilepsy Foundation, 12 Nov. 2004.

4 "Birth Defects," Centers for Disease Control and Prevention (CDC), 8 Aug. 2004, CDC, 12 Nov. 2004.

5 "Pregnancy Issues," Epilepsy Foundation, 12 Nov. 2004.

6 Henshaw, SK, "Unintended pregnancy in the United States," Family Planning Perspectives 1998;30(1):24-29.