A seizure is a sudden burst of abnormal electrical activity in the brain. It can lead to a range of symptoms, like twitching or loss of consciousness.

When one or more unprovoked seizures occur, it’s called epilepsy. In 2015, approximately 3.4 million people in the United States had active epilepsy.

There are many types of epilepsy. Different types are linked to different factors. Catamenial epilepsy occurs when seizures are connected to certain phases of your menstrual cycle.

Catamenial epilepsy affects people who were assigned female at birth who have epilepsy. It’s a type of pharmacoresistant epilepsy, meaning it’s poorly managed by medications. This can be stressful and impact your quality of life.

Read on to learn about catamenial epilepsy, along with causes and possible treatments.

In catamenial epilepsy, seizures become worse or more frequent during certain times of the menstrual cycle. The seizures are related to hormonal fluctuations that occur during the menstrual cycle, as well as puberty, pregnancy, and menopause.

Catamenial epilepsy is also known as catamenial disorder or menstrual seizures.

Catamenial epilepsy affects approximately 40 percent of people assigned female at birth who have epilepsy. Within this group, those who are of reproductive age are more likely to have the condition.

Catamenial epilepsy can cause a worsening of seizures during specific times in the menstrual cycle. Seizures can worsen in people with either focal or generalized epilepsy.

Focal seizures, which affect one part of the brain, may cause symptoms like:

  • jerking
  • dizziness
  • tingling
  • blank staring
  • confusion
  • repetitive motions
  • feeling of fullness in the stomach
  • sudden emotional changes
  • vision changes

Generalized seizures affect both sides of the brain. Common symptoms include:

  • jerking
  • twitching
  • stiffness
  • falling
  • loss of consciousness
  • confusion
  • crying out
  • loss of control of bladder or bowel function
  • lack of breathing

If you have a catamenial epilepsy, the seizures will become worse or more frequent during certain times.

These changes can happen in different patterns:

  • Perimenstrual (C1). Perimenstrual seizures occur just before or during your period. This pattern is called catamenial type 1 or C1.
  • Periovulatory (C2). If seizures worsen at ovulation, it’s known as a periovulatory pattern. It’s also referred to as catamenial type 2 or C2.
  • Luteal phase (C3). In catamenial type 3 or C3, seizures get worse during the luteal phase. The luteal phase occurs in the second half of your cycle.

The exact cause of catamenial epilepsy is unclear. But according to a 2019 study, it’s related to the hormonal changes that happen during the menstrual cycle.

This includes:

Reduced progesterone

The C1 pattern is sometimes due to changes in progesterone. The C3 pattern is caused by inadequate progesterone secretion during the luteal phase.

Progesterone is a hormone that increases after ovulation each month. It thickens the lining of your uterus, which prepares your body for a fertilized egg.

The hormone also has natural anticonvulsant effects. It helps make neurosteroids in the brain, which control the excitability of nerve cells.

However, progesterone drops just before and during your period. It also decreases during the luteal phase.

Increased estrogen

C1 and C2 patterns are related to changes in estrogen. Right before menstruation the progesterone decreases faster than estrogen leading to more estrogen than progesterone which is what is thought to trigger pre-menstrual seizures.

Estrogen is the main reproductive hormone in people assigned female at birth. It helps regulate the menstrual cycle and growth of the uterine lining.

Unlike progesterone, estrogen has proconvulsant effects. The mechanism behind these effects is unknown.

Estrogen increases around ovulation. Thus, its proconvulsant effects can cause seizures in a C2 pattern.

Along with your medical history, several tests can be used to diagnose catamenial epilepsy:

  • Electroencephalogram. An electroencephalogram (EEG) measures the brain’s electrical activity. An EEG will allow a doctor to identify abnormal patterns.
  • Imaging scans. Imaging scans, like magnetic resonance imaging (MRI) and computed tomography (CT) scans, create detailed images of your brain. This can show where the seizures are happening.
  • Seizure and period log. A doctor can use this information to determine if your seizures are related to your menstrual cycle.
  • Temperature log. A record of your body temperature can also help your doctor find patterns between seizures and periods.

Treatment requires multiple therapies. These include:

Anti-epilepsy drugs

The first line of treatment is anti-epilepsy drugs (AEDs).

However, the seizures usually continue. This is due to the hormonal fluctuations that happen during the menstrual cycle. Some AEDs can alter levels of reproductive hormones, which may continue triggering seizures.

You may need to take higher doses when you’re most likely to have worse seizures. You might also have to take multiple AEDs.

Hormonal drugs

Hormonal drugs are used in combination with AEDs. This includes drugs to increase progesterone or reduce estrogen.

Examples include:

The best option depends on whether you have regular or irregular periods.

Hormonal drugs might negatively interact with some AEDs. A neurologist can help you choose the safest hormonal drug for your situation.

Dietary changes

If certain foods trigger seizures, you’ll likely need to avoid them. You may also be asked to follow a seizure diet, or a low-carbohydrate diet, like the modified Atkins diet.


In severe cases, you may need surgery. This involves removing the ovaries, which completely stops menstruation and can provide relief. People with catamenial epilepsy may also benefit from epilepsy surgery targeting the area of the brain where the seizures originate.

If you’ve already been diagnosed with catamenial epilepsy or epilepsy, continue seeing your doctor. They can monitor your progress and adjust your medication as necessary.

You should also see a doctor if you:

  • have a seizure for the first time
  • have more or worse seizures than usual
  • are injured during a seizure
  • have a long seizure
  • have a seizure while pregnant
  • have difficulty waking up after a seizure

Since catamenial epilepsy responds poorly to AEDs, controlling your seizures requires a multilayered approach. Otherwise, if the condition goes untreated, it can lead to brain damage and poor quality of life.

For the best outlook, you’ll need to work closely with your healthcare team. This involves developing a plan to manage your seizures.

Your seizure management plan will include:

  • multiple medications
  • safety precautions
  • lifestyle changes

Here’s how catamenial epilepsy affects the following scenarios:

  • Daily life. To properly manage seizures, take your medication according to your doctor’s directions. Be sure to attend your regular checkups.
  • Fertility. Some AEDs can negatively affect fertility or the effectiveness of hormonal drugs. If you want to have children, tell your doctor so that they can take extra steps to minimize reproductive issues.
  • Pregnancy. Approximately 35 percent of people with catamenial epilepsy have worse seizures during pregnancy. Since seizures and some AEDs can harm an unborn baby, it’s important to work closely with your doctors while pregnant.

Catamenial epilepsy is when the severity of seizures is linked to your menstrual cycle. The seizures get worse or more frequent during certain phases due to hormonal fluctuations.

If you have epilepsy, see your doctor any time your seizures get worse. They can help you determine whether these changes are related to your menstrual cycle. If you have catamenial epilepsy, treatment will focus on managing seizures with anti-epilepsy drugs, hormonal therapy, and lifestyle changes.