From the Guidelines
Seizure attacks in women before or after menstruation are primarily caused by hormonal fluctuations during the menstrual cycle, with estrogen lowering the seizure threshold and progesterone having protective anticonvulsant properties 1. The relationship between seizures and the menstrual cycle is complex, involving various factors such as hormonal changes, fluid retention, and the effects of anti-seizure medications.
- Hormonal fluctuations: Estrogen and progesterone levels change significantly throughout the menstrual cycle, affecting the seizure threshold.
- Fluid retention: Before menstruation, fluid retention can decrease the concentration of anti-seizure medications in the bloodstream, making them less effective.
- Anti-seizure medications: Certain medications, such as valproate, can have endocrine effects, including weight gain, polycystic ovaries, and hyperandrogenism 1. Some women may benefit from adjusting their anti-seizure medication dosage around their period, with common medications including levetiracetam (Keppra), lamotrigine (Lamictal), or valproate (Depakote) 1.
- Hormonal treatments: Progesterone supplements or hormonal contraceptives may help stabilize hormone levels and reduce seizure frequency.
- Lifestyle modifications: Maintaining consistent medication levels, getting adequate sleep, managing stress, and avoiding seizure triggers like alcohol are also important for managing catamenial seizures. Tracking seizures in relation to menstrual cycles can help identify patterns and guide treatment. It is essential to consider the potential effects of anti-seizure medications on reproductive endocrine disorders, such as polycystic ovary syndrome (PCOS), hypothalamic amenorrhoea, and functional hyperprolactinaemia 1.
From the Research
Causes of Seizure Attacks in Women Before or After Menstruation
- Seizure attacks in women before or after menstruation can be caused by hormonal fluctuations during the menstrual cycle, specifically the changes in progesterone and estrogen levels 2, 3.
- The reduction in progesterone levels premenstrually and reduced secretion during the luteal phase can increase the risk of seizures, as progesterone has anticonvulsant effects 2.
- A pre-ovulatory surge in estrogen can also contribute to seizure exacerbation, although the exact mechanism is uncertain 2.
- Catamenial epilepsy, which affects around 40% of women with epilepsy, describes a worsening of seizures in relation to the menstrual cycle, with vulnerable days including perimenstrually, at ovulation, and during the luteal phase 2.
- Studies have shown that irregular menstrual cycles and seizure worsening during the premenstrual, menstrual, catamenial, or ovulatory periods are common in women with epilepsy, particularly those with mesial temporal lobe epilepsy (MTLE) and extratemporal focal epilepsy (ETFE) 4, 5.
Hormonal Influences on Seizure Activity
- The female reproductive hormones have opposing effects on neuronal excitability, with estrogens generally imparting a proconvulsant tone and progestogens having anticonvulsant effects 3.
- Fluctuations in serum progesterone and estrogen levels throughout the menstrual cycle can increase or decrease the risk of seizure occurrence based on the serum estradiol/progesterone ratio 3.
- Hormonal therapy, including progesterone and its metabolite allopregnanolone, has been explored as a treatment option for patients with epilepsy, particularly those with catamenial epilepsy 2, 3.
Clinical Considerations and Treatment Options
- Women with epilepsy, particularly those of childbearing age, require careful consideration of their treatment options, including the potential interactions between antiepileptic drugs (AEDs) and contraceptives 6.
- Planned pregnancy and counseling before conception are crucial, including discussions on folic acid supplementation, medication adherence, and the risk of teratogenicity 6.
- Treatment options for catamenial epilepsy remain limited, and further research is needed to develop effective therapies for this condition 2, 6.