March 9, 2021

Catamenial epilepsy: what you need to know

About Epilepsy

Catamenial epilepsy affects many women. Learn what it is, why it happens and how it’s treated. We also look at how pregnancy and menopause are affected.

Have you noticed that you have more seizures at certain times of the month? This could be a sign of catamenial epilepsy. Catamenial epilepsy is a type of epilepsy where seizures are linked to a woman’s menstrual cycle.

Let's learn more about what catamenial epilepsy is, its symptoms and the way it's treated. We also explore how the menopause and pregnancy affect it.

Two smiling women with catamenial epilepsy

What is catamenial epilepsy?

The word ‘catamenial’ means something that is related to menstruation (the period).  

Some women with epilepsy notice that they have more seizures at certain times in their menstrual cycle. At different stages of the cycle there are different levels of the hormones estrogen and progesterone in your body. Hormones are like chemical messengers which tell your body to do different things.

When there is more estrogen in your system, your brain cells may become more excitable - this means they are more likely to discharge electricity and cause a seizure. Progesterone on the other hand is an anticonvulsant. It ‘calms’ the cells in your brain, making it less likely you'll have a seizure.

If you have catamenial epilepsy, these changes in hormone level affect when you have seizures (it affects different women in different ways):

  • Before your period: There’s a drop in progesterone which could trigger seizures
  • During and after your period: There’s more estrogen in your body which makes your brain cells more excitable

It is unclear exactly how many women have catamenial epilepsy. It’s believed to be around one in 10, although some studies suggest as much as 70% of women with epilepsy have catamenial seizures.

What are the symptoms of catamenial epilepsy?

The main symptom of catamenial epilepsy is a noticeable increase in the number of seizures you have at certain times of the month. It will normally follow a pattern. For example, if you usually have your period in the first week of the month, you might also notice that you have most - if not all - your seizures at this time. This would indicate that you are having catamenial epilepsy seizures.

Women who have catamenial epilepsy can have all kinds of seizures, including focal aware (simple partial), focal impaired aware (complex partial), absence seizures and tonic clonic seizures.

What about catamenial epilepsy and menopause?

During the menopause there are big changes in hormone levels in your body. If you have catamenial epilepsy you may notice an increase in the number of seizures you have at the beginning of the menopause. But, later on you may see that there is a decrease. This is because there are lower levels of estrogen in your body after the menopause.

Catamenial epilepsy and pregnancy

There are also big changes in hormone levels during pregnancy, and this may affect catamenial seizures. Research suggests that some women with catamenial epilepsy experience fewer seizures during pregnancy. This is because the normal monthly cycle of hormones is put on hold. But other studies have found there may actually be an increase in seizure activity. 

If you have catamenial epilepsy, it’s a good idea to speak with your epilepsy treatment team about how to prepare for pregnancy.

Treatment of catamenial epilepsy seizures

There are a few different treatment options if you are having catamenial seizures. These include:

  • Hormonal treatments: Women with catamenial epilepsy are more likely to have seizures when there are lower levels of progesterone in their systems. Hormone therapy may help here. It aims to balance out the hormone levels in your body by giving you a ‘boost’ in progesterone at certain times of the month.
  • Oral contraceptive (the pill): This works in a similar way to hormone therapy by changing the balance of hormones in your body.  
  • Anti-seizure drugs: These work in different ways to reduce the excitability of your brain cells.

Read about Nessa's experience of living with catamenial epilepsy here

Managing catamenial epilepsy

Scientists are still learning about catamenial epilepsy, and more research is needed to develop better treatments. You might find it useful to record all your seizures in Epsy and note down when they happen in relation to your period. This can help your doctor understand your condition patterns better and provide treatment that is personalized to you.

To learn more about issues affecting women with epilepsy read our blog.