Women's Health

Seizures and the Menstrual Cycle

In some women, seizure frequency is connected to hormonal changes that occur throughout the menstrual cycle. This is called Catamenial epilepsy. With this type of epilepsy, the majority of seizures happen more frequently at certain times of a woman’s menstrual cycle, particularly around the beginning of her period, around ovulation, and/or during the latter half of the menstrual cycle. Women who notice a connection between their menstrual cycle and seizure frequency should discuss this with their doctor, as there may be treatment options available to improve seizure control.

Birth Control Pills

Some anti-seizure medications can reduce the effectiveness of birth control pills, and birth control pills can reduce the effectiveness of some anti-seizure medications. Ontario’s Epilepsy Implementation Task Force recommends that physicians avoid prescribing “enzyme inducing anti-seizure medications” to women using birth control pills. These medications include Phenytoin, Phenobarbital, and Carbamazepine. If you are taking anti-seizure medications and birth control pills, talk to your doctor about your options.

  • The vast majority of women with epilepsy will have healthy pregnancies and healthy babies.
  • Women with epilepsy whose seizures are well controlled are likely to remain seizure-free during pregnancy.
  • Women with epilepsy who smoke while pregnant have increased risk of premature contraction and premature labor and delivery.
  • As of 2014, the safest medications appear to be Lamotrigine and Levetiracetam according to the latest review of the North American Pregnancy Registry.
  • Ideally, women should work with their health care provider before becoming pregnant to achieve the best seizure control possible with the fewest number and lowest dose of anti-seizure medication(s) possible.
  • Some women may be tempted to stop taking their epilepsy medication once they find out they are pregnant. However, women should never stop taking medication without first consulting their doctor, as this could result in an increase in seizures, which could harm the mother or baby.
  • Work with your doctor to aim for seizure freedom before getting pregnant.
  • Work with your doctor to simplify your medication regimen, aiming for monotherapy (managing seizures with one medication) at the lowest dose possible.
  • Using folic acid (1-5 mg/day) is highly recommended, starting before conception.
  • Your doctor should monitor your anti-seizure medication levels more often during each trimester of pregnancy.
  • Your doctor should monitor you closely for complications in your pregnancy.
  • If you smoke, it is best to quit smoking if you intend to become pregnant.
  • For most women with epilepsy, breastfeeding is recommended and safe.
  • If you are at risk of osteoporosis, work with your doctor to avoid the group of medications called “enzyme-inducing” anti-seizure medications. This group of anti-seizure medications can increase the rate of fractures.
  • If you take an enzyme-inducing anti-seizure medication, get screened for osteoporosis regularly.
  • Take Vitamin D and Calcium supplements daily.
  • * Disclaimer: This material is intended to provide basic information about epilepsy to the general public. It is not intended to, nor does it, constitute medical advice. Readers are warned against changing medical schedules or life activities based on the information it contains without first consulting a physician.

Adapted from: Provincial Guidelines for the Management of Epilepsy in Adults and Children (Epilepsy Implementation Task Force); Epilepsy in Pregnancy: A Fine Balance, Dr. Esther Bui (Epilepsy Toronto)

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