Birth Control and Epilepsy

By: Aaliyah Ellison-McPeters

Photo Credit:

What is Birth Control?

Birth control, also referred to as contraception or family planning, is devices, medicines, or surgeries that  prevent pregnancy. Various methods have different techniques to avoid conception, such as preventing  sperm cells from reaching egg cells, damaging sperm, preventing ovulation, and more. A few standard methods include barriers: male and female condoms, diaphragms, and cervical caps. These devices will  prevent sperm from reaching an egg cell. Hormonal methods that prevent ovulation, the part of the  menstrual cycle responsible for releasing an ovum cell from the ovaries, include birth control pills,  hormonal IUDs, or injections. Sterilization, tubal ligation for women, or vasectomies for men, prevent  pregnancy permanently unless surgically reversed.

Other non-hormonal and less invasive options, such as spermicide or vaginal gel, these products limit the  movement of sperm cells to prevent them from reaching the egg. Fertility awareness methods focus on  which days you are fertile. Fertile days are tracked by taking basal body temperature, checking cervical  mucus, and using ovulation predictor kits. To avoid pregnancy, one doesn’t have intercourse during her  fertile window; if she does, she’ll use a barrier method. Emergency contraceptives, Plan B One-Step, prevent pregnancy after unprotected sex by delaying ovulation. Emergency contraceptives cannot be used  in place of a standard form of birth control, and there are often limitations that can affect whether it’ll  work, such as weight. If you have already ovulated, then it won’t be effective.

AEDs and Birth Control Effectiveness

Some anti-epileptic drugs are enzyme-inducing and synthesize enzymes cytochrome P450 or CYP450.  These enzymes are necessary for the metabolism of many medications. There are more than fifty enzymes  apart of CYP450, and six are commonly found in approximately 90% of drugs, the most prominent ones being CYP3A4 and CYP2D6. AEDs with this feature can cause female sex hormones to decrease in  women taking oral forms of birth control or any methods that contain hormones, potentially raising the  risk of unplanned pregnancy. Enzyme-inducing AEDs increase the level of enzymes that break down  hormones in the body, which can affect hormonal birth control methods. The mini pill or the  progesterone-only pill is also less effective for preventing pregnancy than the combined pill containing synthetic female hormones estrogen and progestogen. The mini pill thickens the cervical mucus and  thins the uterine lining of the uterus. It prevents sperm from reaching the egg and a fertilized egg from  implanting along the womb’s lining. The mini pill contains progestins, synthetic forms of progesterone,  and anti-epileptic drugs, which can increase the metabolism of progestins, decreasing the hormone’s  effectiveness. Anti-epileptic medicines that don’t have CYP450 do not demonstrate to affect the efficacy of oral contraceptives and, in turn, do not increase the risk of unplanned pregnancy.

Finding Your Birth Control Method

When choosing the best birth control method, selecting the most convenient, effective contraceptive and  affordable medication is essential. For epileptic women, birth control with few to no hormones is a good  choice. These include barrier methods such as condoms or cervical caps, natural family planning,  sterilization, or copper IUDs. For convenience, copper IUDs are inserted into the uterus to prevent  pregnancy and can last up to five-ten years. The effectiveness of the other options depends on the user.  Male condoms are about 98% effective, and female condoms are 95% effective. Cervical caps are  approximately 86% for women who have never given birth and 71% effective for those who have.  Fertility awareness methods are 98% effective with perfect use and 77% effective with typical use. These  estimates are also based on which fertility awareness method you choose and which are more effective if  you work with a nurse, doctor, or counselor knowledgeable in the technique.


Birth Control Methods & Options | Types of Birth Control. (n.d.). Retrieved May 5, 2023, from

Birth control options: Things to consider. (n.d.). Mayo Clinic. Retrieved May 5, 2023, from

Carl, J. S., Weaver, S. P., Tweed, E., & Edgerton, L. (2008). Effect of Anti-epileptic Drugs on Oral  Contraceptives. American Family Physician, 78(5), 634–635.

Contraception and epilepsy | Epilepsy Society. (2020, March 15). epilepsy/women-and-epilepsy/contraception-and-epilepsy

Lynch, T., & Price, A. (2007). The Effect of Cytochrome P450 Metabolism on Drug Response,  Interactions, and Adverse Effects. American Family Physician, 76(3), 391–396.

Patel, T., & Grindrod, K. A. (2020). Antiseizure drugs and women: Challenges with contraception and  pregnancy. Canadian Pharmacists Journal : CPJ, 153(6), 357-360.

Reddy, D. S. (2010). Clinical pharmacokinetic interactions between anti-epileptic drugs and hormonal  contraceptives. Expert review of clinical pharmacology, 3(2), 183.

Reimers, A., Brodtkorb, E., & Sabers, A. (2015). Interactions between hormonal contraception and anti epileptic drugs: Clinical and mechanistic considerations. Seizure, 28, 66-70.

Read More