Epilepsy and contraception

This page is about contraceptive options in the UK. If you are looking for information about what is available in other countries, please contact your local epilepsy organisation who should be able to help you.

We have produced this information to help you understand how different methods of contraception may interact with different anti-epileptic drugs. This will help you to decide which methods of contraception may be the most suitable for you. You may find it helpful to discuss this information with your own family doctor or local sexual health clinic. They will be able to offer you more detailed advice and information about your individual contraceptive needs.

  

Planning a pregnancy

If you have epilepsy, it is advisable for every pregnancy to be planned, wherever possible. This is because women with epilepsy have a slightly higher risk of complications during pregnancy than women who don’t have epilepsy. However, if your pregnancy is planned carefully, with advice from your epilepsy specialist or epilepsy specialist nurse, these risks may be minimised.

If you are sexually active and you want to avoid getting pregnant, it’s important to find a form of contraception that is as effective as possible for you.

  

Anti-epileptic drugs and contraception

Some anti-epileptic drugs (AEDs) are ‘enzyme-inducing’. Enzyme-inducing AEDs can speed up the way that your body uses the hormones that are used in some types of contraception. This can make the contraceptive less effective and could lead to an unplanned pregnancy.

You can find out from the table below if you are taking enzyme-inducing or non-enzyme inducing AEDs.

 

Enzyme-inducing anti-epileptic drugs  

Non-enzyme-inducing anti-epileptic drugs 

  • carbamazepine
  • eslicarbazepine acetate 
  • oxcarbazepine
  • phenobarbital
  • phenytoin
  • primidone
  • topiramate
  • clonazepam
  • ethosuximide
  • gabapentin
  • lamotrigine*
  • levetiracetam
  • pregabalin
  • sodium valproate
  • tiagabine
  • vigabatrin

*Lamotrigine is not enzyme inducing, but may still reduce the effectiveness of some types of contraception.

  

How will my anti-epileptic drugs affect my choice of contraception? 

Combined oral contraceptive pill (COC) – ‘the Pill’

The (COC) contains the hormones oestrogen and progestogen.
You usually take a tablet every day for 21 days and then you take a break for seven days.

If you take enzyme-inducing drugs

Enzyme-inducing anti-epileptic drugs can make the combined oral contraceptive pill (COC) less effective, which could lead to an unplanned pregnancy.

You might still choose to take the COC, but you should take a COC containing a minimum initial dose of 50 micrograms of oestrogen and a double dose of progestogen. This will increase its effectiveness in preventing pregnancy.

If you have breakthrough bleeding, this may be a sign that the COC is not working effectively. In this case, your doctor may increase the dose of oestrogen to 75 micrograms or 100 micrograms each day. They may also suggest ‘tricycling’. This means taking three packs of the COC continuously, then taking a four-day break before starting the COC again.

Even if you take a higher-dose of the COC, its effectiveness may still be reduced, increasing your risk of an unplanned pregnancy. Your doctor or local sexual health clinic will be able to offer you more individual advice about taking the COC.

If you take non-enzyme inducing drugs

Evidence suggests that this could be an effective form of contraception for you unless you take lamotrigine.

Research on a small group of women has indicated the following.

  • Lamotrigine may make the COC less effective, which increases the risk of unplanned pregnancies.
  • The COC may reduce the amount of lamotrigine in the bloodstream, which increases the risk of seizures. 

If you take lamotrigine and want to take the COC, it is advisable to discuss this further with your GP or epilepsy specialist. They may need to increase your dosage of lamotrigine.

 

Condoms

These are rubber barriers that fit over the man’s penis.
They do not involve the use of hormones.

If you take enzyme-inducing drugs or non-enzyme inducing drugs

This could be an effective form of contraception for you.

 

Contraceptive implants (Implanon)

Contraceptive implants contain the hormone progestogen.
An implant is one or more small tubes which are implanted under the skin in your upper arm. They slowly release the hormone into your body. An implant can last up to three years.

If you take enzyme-inducing drugs

These are not recommended, because enzyme-inducing anti-epileptic drugs make contraceptive implants much less effective in preventing pregnancy.

If you take non-enzyme inducing drugs

Evidence suggests that this could be an effective form of contraception for you.

 

Contraceptive patch

The contraceptive patch contains the hormones oestrogen and progestogen.
You stick the patch on part of your body and it slowly releases the hormones through your skin and into your body. You usually apply a new patch once a week for three weeks, then you take a break for seven days.

If you take enzyme-inducing drugs

These are not recommended, because enzyme-inducing anti-epileptic drugs make the contraceptive patch much less effective in preventing pregnancy.

If you take non-enzyme inducing drugs

Evidence suggests that this could be an effective form of contraception for you unless you take lamotrigine.
There is some suggestion that the following may happen.

  • Lamotrigine may make the contraceptive patch less effective, which increases the risk of unplanned pregnancies.
  • The contraceptive patch may reduce the amount of lamotrigine in the bloodstream, which increases the risk of seizures. 

If you take lamotrigine and want to use the contraceptive patch, it is advisable to discuss this further with your GP or epilepsy specialist. They may advice you to choose a different method of contraception. 

 

Depo-Provera contraceptive injection

This injection contains the hormone progestogen.
It is injected into a muscle and slowly releases the hormone into the body. You usually need to have the injection every twelve weeks.

If you take enzyme-inducing drugs or non-enzyme inducing drugs

This may be an effective form of contraception for you. However, your doctor may suggest that you have the Depo-Provera injection every 10 weeks (instead of the usual 12 weeks).

Note: the Depo-Provera injection can speed up bone loss, as can some anti-epileptic drugs (AEDs), which can lead to a condition called osteoporosis. This causes bones to become thinner and more brittle so they can break more easily. If you take AEDs and are considering using the Depo-Provera injection, it would be advisable to seek advice about osteoporosis from your doctor.

More information about osteoporosis

 

Diaphragms and caps

These are rubber or plastic barriers that fit inside your vagina.
They do not involve the use of hormones.

If you take enzyme-inducing drugs or non-enzyme inducing drugs

This could be an effective form of contraception for you.

 

Emergency contraception – ‘the morning-after pill’

This is a tablet which contains a high dose of the hormone levonorgestrel.
It is a form of emergency contraceptive and can be used within 72 hours of having unprotected sex or when your contraceptive has failed. Guidelines say that it should not be used as a regular contraceptive.

If you take enzyme-inducing drugs

You can use the morning-after pill but you will need to take twice the dose that women not taking enzyme-inducing drugs take.

Current guidelines suggest that you should take 1.5 milligrams of levonorgestrel (morning-after pill) immediately and another 1.5 milligrams 12 hours later.

In the UK, this dose of levonorgestrel must be prescribed by a doctor.

If you take non-enzyme inducing drugs

Evidence suggests that the effectiveness of the usual dose of emergency contraception (a single tablet) would not be affected by your AEDs.

 

Femidoms

These are rubber barriers that fit inside your vagina.
They do not involve the use of hormones.

If you take enzyme-inducing drugs or non-enzyme inducing drugs

This could be an effective form of contraception for you.

 

Intrauterine devices – ‘the coil’

This is a device made from plastic and copper that is fitted into your womb and prevents you from becoming pregnant.
The device can stay in your womb for three to ten years.

If you take enzyme-inducing drugs or non-enzyme inducing drugs

This could be an effective form of contraception for you.

 

 

Intrauterine systems (Mirena coil)

This contains the hormone progestogen.
It is similar to an intrauterine device, but it also releases the hormone progestogen directly into your womb. It can stay in for up to five years (or longer if you are over the age of 45).

If you take enzyme-inducing drugs or non-enzyme inducing drugs

Evidence suggests that this could be an effective form of contraception for you.

 

 

Natural birth control (Rhythm and Persona methods)

Natural birth control methods rely on you accurately tracking your menstrual cycles, to identify the days when you are most fertile and likely to ovulate (release an egg). To reduce the risk of pregnancy, you should avoid sex on the days that you have identified that you are fertile. There are two main methods of natural birth control - rhythm and persona.

If you take enzyme-inducing drugs or non-enzyme inducing drugs

Rhythm method

This involves you counting the days of your menstrual cycle to decide when you are most fertile. You must have regular and stable menstrual cycles for this to be effective.

The rhythm method is not a recommended form of birth control if you have epilepsy and/or take anti-epileptic drugs, because your menstrual cycle may be affected by your epilepsy. Also, generally speaking, it is far less effective than other forms of contraception.

Persona method

This involves testing your urine for hormonal changes, which indicate when you are fertile.

The Persona method of birth control is not recommended as a reliable form of birth control if you have epilepsy. This is because your ovulation and the levels of hormones in your urine can be affected by both your seizures and your anti-epileptic drugs.

 

Noristerat contraceptive injection

This injection contains the hormone progestogen.
It is injected into the muscle of your buttock and slowly releases the hormone into your body. You usually need to have the injection every eight weeks.

If you take enzyme-inducing drugs

This form of contraception is not recommended, because your AEDs make it less effective.

If you take non-enzyme inducing drugs

Evidence suggests that this could be an effective form of contraception for you.

 

Progestogen-only pill – ‘the mini-pill’

The progestogen-only pill (POP) only contains the hormone progestogen.
You take a tablet every single day.

If you take enzyme-inducing drugs

This form of contraception is not recommended, because your AEDs make it less effective.

If you take non-enzyme inducing drugs

Evidence suggests that this could be an effective form of contraception for you.

November 2008

 

More in this section: 

  • Sexual development (puberty)
  • Sex life
  • Your periods (the menstrual cycle)
  • Contraception
  • The menopause and HRT
  • Epilepsy and fertility
  • Planning a baby
  • Scans and tests during pregnancy
  • Giving birth
  • Breastfeeding
  • Caring for children
  • Inheriting epilepsy
  • How you can help Epilepsy Action
  • Epilepsy Mine

  • We can provide references and information on the source material we use to write our epilepsy advice and information pages. Please contact our Epilepsy Helpline by email at helpline@epilepsy.org.uk.

    Comments

    I was just reading your page on women & epilepsy / contraception. It says that the Mirena Coil could be a suitable contraceptive for women taking enzyme inducing anti convulsants. I have a coil fitted and it is a non-hormonal coil (so this is not a Mirena coil). This is because the hormones in a Mirena coil would possibly interact with my medication and therefore be ineffective.
    I could have been given duff advice, but through several years of trying hard not to get pregnant while on Topiramate (and now Keppra too) I thought I would share my experience.