Guidelines confirm safety of pregnancy in women who have epilepsy—with caveats
Otherwise healthy women can expect an uneventful pregnancy and delivery, provided they avoid valproate, seizures, and smoking
IN THIS ARTICLE
“Levels of seizure medications in the blood tend to drop during pregnancy, so checking these levels and adjusting the medication doses should help to keep the levels in the effective range and the pregnant woman seizure-free,” said Harden.
Antiepileptic drugs should be administered at the lowest dosage and lowest plasma level that protects against tonic-clonic seizures and other complex partial seizures.5
to protect the fetus
Here is a summary of the main recommendations in the guidelines from the American Academy of Neurology and American Epilepsy Society:
Avoid certain drugs; discourage smoking
- Avoid first-trimester exposure to the antiepileptic drug valproate because of its link to an increased risk of fetal malformation and cognitive impairment in children. Also avoid epilepsy drug polytherapy during the first trimester.
- Besides avoiding valproate and antiepileptic drug polytherapy during the first trimester, women who have epilepsy should avoid these regimens throughout pregnancy to prevent adverse cognitive outcomes in the infant.
- Avoid prescribing phenytoin and phenobarbital during pregnancy.
- Women who take antiepileptic drugs are probably at increased risk of delivering a small-for-gestational-age baby and, possibly, delivering a newborn with an Apgar score below 7 at 1 minute.
- Women who have epilepsy and who smoke may increase the risk that they will develop premature contractions, premature labor, and premature delivery.
Monitor levels of some drugs
- Monitor levels of lamotrigine, carbamazepine, and phenytoin during pregnancy. Also monitor levels of levetiracetam and oxcarbazepine (a monohydroxy derivative). Blood levels of antiepileptic drugs tend to drop during pregnancy, and the dosage may need to be adjusted.
Seizure-free pregnancy is possible
- Counsel women who have epilepsy that remaining free from seizures for at least 9 months before pregnancy greatly increases the likelihood that they will remain seizure-free during pregnancy.
Folic acid may be beneficial
- Consider giving women who have epilepsy at least 0.4 mg of folic acid daily before they become pregnant, as it appears likely to lower the risk of major congenital malformation. It is unclear whether a higher daily dosage offers greater protective benefits.
Counsel the mother about breastfeeding concerns
- Women who have epilepsy and who choose to breastfeed should be counseled that primidone and levetiracetam probably pass into breast milk in significant amounts. In addition, gabapentin, lamotrigine, and topiramate may pass into breast milk in significant amounts. In contrast, valproate, phenobarbital, phenytoin, and carbamazepine probably do not pass into breast milk in clinically important amounts.
Guidelines were based on a review of the literature
The guidelines were developed after a review of all scientific studies available on each topic and were published in the online issue of the journal Epilepsia.1-3 Their development was supported in part by the Milken Family Foundation.
“For too long, women living with epilepsy have feared the added risk of premature birth and other consequences of both their epilepsy and their medications,” said Howard R. Soule, PhD, chief science officer for the Milken Family Foundation. “The results of this project will help relieve the worries of these women and their families.”
Do not withdraw antiepileptic drugs during pregnancy
Some physicians attempt to discontinue an antiepileptic drug when a woman has gone 2 years without experiencing a seizure.5 In this scenario, the likelihood that seizures will recur within 6 and 12 months is 12% and 32%, respectively.6 Because of the risk that seizures will recur, and the increased likelihood of adverse outcomes associated with seizures during pregnancy, antiepileptic medication should not be discontinued during gestation.
Nor should a woman attempt to transition from one antiepileptic drug to another during pregnancy solely for the purpose of reducing teratogenicity.5 Doing so could precipitate seizures and exposes the fetus to the potentially hazardous effects of an additional antiseizure medication during a critical period. Moreover, there may be no advantage associated with switching drugs once a pregnancy has been established.7
Screen for malformations rigorously
Comprehensive screening for fetal anomalies early in the pregnancy is recommended for two main reasons:
- If a malformation is identified, the mother has the option of terminating the pregnancy
- Even if the patient decides not to terminate a gestation in which fetal anomaly has been identified, the information may help the practitioner determine the best mode and place of delivery.
Cesarean delivery may be warranted if the mother
has had recent seizures
Although most women who have epilepsy can expect to have a normal vaginal delivery, elective cesarean should be considered if the mother has experienced frequent seizures during the third trimester, or if she has a history of stress-related status epilepticus.5
