Seizures are often linked to menarche, the menstrual cycle and menopause

Seizures are exacerbated by hormones

There maybe a higher incidence of infertility and contraceptive failure due to effects of some anti epileptic drugs

Sexual function and reproductive health are influenced by seizures and anti epileptic drugs

Pregnancy in a woman with epilepsy causes increased risk to mother and childs

Seizures are linked to the menses because sex hormones alter the excitability of neurons in the cerebral cortex

Estrogens can lower seizure threshold resulting in an increase in the frequency of interictal spikes in the EEG and seizures clinically

Progestins have the opposite effect and may protect against seizures

The presence or absence of ovulation (releasing of an ovum or egg from the ovary) affects the likelihood of seizure

Seizures may increase a few days before the menses and in the first 2-3 days of bleeding, perhaps precipitated by the rapid decline in progesterone levels.

Seizure frequency may also increase at the time of ovulation as a result of the rise in oestrogen levels

When the cycle is ovulatory, there is a reduction in seizures during the luteal phase (days 17 to 24) due to protection by the increased progesterone levels

With anovulatory cycles, the progesterone secreting corpus luteum is not formed and estrogen levels remain high

Hence, anovulatory cycles are associated with a pattern of increased seizures during the entire second half of the menstrual cycle

To determine if there is a catamenial pattern, patients should chart menses along with basal body temperature and seizures for several months. The basal body temperature determines ovulation.

Progesterone levels can be measured on day 22 of the menstrual cycle. A level lower than 5 ng/ml on day 22 indicates an anovulatory cycle

A supplemental increase in the daily dose of the maintenance antiepileptic drug at the expected time of seizure will prevent them from occurring

Acetazoleamide (Diamox) has also been used with limited success

Hormonal manipulation is not usually done

The choice of birth control for women with epilepsy must take into account the high failure rate of hormonal contraception in women taking hepatic enzyme inducing drugs

The hepatic p450 system also metabolises sex steroids, and the enhanced metabolism induced by some anti epileptic drugs leads to lower hormonal levels and reduced contraceptive efficacy

Oral contraceptives can still be used but higher doses are needed

Anti epileptic drugs that induce Hepatic enzyme are Carbamazepine (Tegretol) Felbamate, Phenobarbitone (Gardenal), Phenytoin Sodium (Eptoin, Dilantin) Primidone (Mysoline) and Topiramate (Topamac)

Contraceptive failure does not occur with Valproate, Gabapentin, Lamotrigine