It is known that women suffering from temporal lobe epilepsy may frequently present reproductive endocrine disorders (REDs). We hypothesized that a high occurrence of REDs could be found also in primary generalized epilepsy (PGE), and therefore investigated the hormonal and ovarian echographic profiles in 20 PGE female patients of reproductive age. Fourteen reported normal menstrual cycles, while 6 complained of longstanding menstrual irregularities. All but three patients were receiving antiepileptic drug (AED) therapy. In all subjects, the basal levels of gonadotropins, prolactin, and gonadal steroids were assayed. The response of luteinizing hormone (LH) to gonadotropin-releasing hormone was also investigated and ovarian ultrasonographic findings were evaluated. In five of six patients with menstrual problems (25% of the group), a well-defined RED was diagnosed (polycystic ovarian disease in three cases and hypothalamic ovarian failure in two). The 14 patients with normal menstrual cycles showed an elevation of mean basal follicle-stimulating hormone and prolactin, and a blunting of mean LH response. Our results suggest that a high occurrence of REDs may be found also in PGE. We hypothesize that a neurotransmitter dysfunction might be the common pathogenetic mechanism resulting in both REDs and PGE. The hormonal alterations observed in the patients with normal menstrual cycles seem to support our hypothesis. Previous data seem to rule out a possible AED effect accounting for the hormonal findings observed in our series. However, further studies are needed to confirm our preliminary results.