Abstracts

RATIONALE: Three types of catamenial epilepsy have been described. The commonest type, Type I, is exacerbation of seizures perimenstrually, i.e., just before or after the onset of menstruation. It has been suggested that fall in serum levels of progesterone premenstrually is the factor responsible for perimenstrual seizure exacerbation. Animal models of catamenial epilepsy support this postulate. Following menarche, menstrual cycles are anovulatory for one to several years in the majority of girls. The ovary produces little progesterone during anovulatory cycles. In the present study, we describe several postmenarcheal girls with anovulatory cycles, little ovarian progesterone secretion and perimenstrual seizure exacerbation. We suggest that factors other than progesterone withdrawal may contribute to perimenstrual seizure exacerbation in some women with catamenial epilepsy.
METHODS: 5 post-menarcheal girls aged 12-17 with remote symptomatic partial complex seizures. ILAE seizure classification was used. Catamenial (perimenstrual) exacerbation of seizures was documented with a three month prospective seizure diary. Mid-luteal (menstrual cycle day 20-22) serum progesterone level was checked during at least one month of documented perimenstrual seizure exacerbation.
RESULTS: Seizures occurred significantly more frequently on menstrual cycles day (-3) to (+3) in all girls. Seizures occurred exclusively perimenstrually (menstrual cycle day [-3]-[-1]) in one girl and mainly premenstrually in another girl. In the remaining girls, seizures occurred with a 2-fold or greater daily frequency perimenstrually compared with other menstrual cycle phases. 3/5 girls had irregular menses, 2/5 had regular menses. 1 girl had late luteal dysphoric syndrome, another girl had significant perimenstrual somatic symptoms. None of the girls had pre- or perimenstrual insomnia or hypersomnia. Mid-luteal serum progesterone levels ranged from 0.1 ng/ml - 1.7 ng/ ml. Mid-luteal serum estrogen levels ranged from 39-68 pg/ml.
CONCLUSIONS: Perimenstrual exacerbation of partial complex seizures can occur in the context of anovulatory cycles and minimal ovarian progesterone secretion. In this context, perimenstrual seizure exacerbation is unlikely to be due to falling serum progesterone levels. Addional, as yet unknown factors, may therefore be implicated in the pathogenesis of perimenstrual seizure exacerbation.
[Supported by: The authors received no financial support for this study.]