Approximately 1 million women of childbearing age in the United States suffer from epilepsy. Concerns these women have about conception and pregnancy involve the choice and use of medication, dosing schedules, and seizure management.
During pregnancy, antiepileptic drug (AED) treatment, hormonal changes, and vitamin deficiency can affect seizure patterns, even for women who have had excellent seizure control in the past. These and genetic factors may increase the risk for birth defects in infants born to epileptic mothers. Although this risk is not significant enough to avoid pregnancy, neurologists and epileptologists (epilepsy specialists) advise diligent care for prospective mothers who suffer, or have suffered, from epilepsy.
Incidence of Epilepsy & Pregnancy
Approximately 20 percent of women with epilepsy experience an increase of episodes during pregnancy. Some experience seizures only while giving birth.
Risks of Epilepsy & Pregnancy to the Mother
Physiological changes that occur during pregnancy may lead to increased frequency of seizures in some women with epilepsy. These changes include the following:
- increased hormone production
- altered eating habits
- increased stress
- altered sleeping patterns
- increased metabolism of AEDs
The hormones estrogen and progesterone increase naturally and steadily during normal pregnancy. Estrogen has been shown to increase seizure activity for epileptics, while progesterone may have an antiseizure effect. Fluctuations in the levels of these hormones during pregnancy can make it more difficult for epileptic women to predict and control seizures.
Generally, sleep deprivation influences seizure frequency for those who suffer from epilepsy. A significant increase in seizure occurrence may result during pregnancy when sleep patterns change. Stress and changes in eating and sleeping habits may also contribute to more frequent seizure activity in some cases.
Levels in the blood of AEDs like phenobarbital, valporate (Depakene), and carbamazepine (Tegretol) decrease during pregnancy. This may result in increased seizure frequency. It is therefore very important to monitor levels closely during pregnancy and to adhere to prescribed treatment.
Any decision to discontinue drug therapy during pregnancy, say if a patient has not experienced seizures for several months, should be made at the discretion of the physician only. Reducing the dosage or discontinuing medication is unsafe because uncontrolled seizures can reduce oxygen or blood supply to the womb, which puts both the woman and the developing fetus at risk.
Also, changes in treatment can immediately alter the concentration of medication in the body, which may lead to sudden changes, especially during pregnancy. For example, a series of seizures can result in an intermittent or prolonged period of unconsciousness, called status epilepticus. Because the woman may collapse during loss of consciousness, the risk to a mother and a developing fetus is high.
Furthermore, an increase in vaginal hemorrhaging, early labor, and eclampsia (toxemia of pregnancy with postpartum convulsions) has been reported in pregnant women with epilepsy.