Background. The low estrogen level is associated with the worsening of the psychotic symptoms in fe males with schizophrenia. We tested the hypothesis that the patients admitted to the hospital in the low-estrogen (low-E) phase require lower neuroleptic dosage and shorter length of hospital stay than the patients admitted in the high-estrogen (high-E) phase. Methods and Results. 51 female patients with schizophrenia were divided into two groups according to their menstrual cycle phase at admission and according to the type of neuroleptic treatment during their hospitalisation. 53 % of them were admitted in the low-E phase. The Student T-test was used for the analysis. The patients of the low-E phase group had lower daily dosage of typical neuroleptics (p<0.001), higher age (p<0.05) and shorter length of hospital stay (p<0.05) than the patients taking atypical neuroleptics. The patients taking typical neuroleptics in the low-E group had lower daily dosage (p<0.05) and they were older (p<0.01) than the patients taking typical neuroleptics in the high-E group. The shorter length of hospital stay (p<0.001) was found in high-E patients with atypical neuroleptics than in low-E patients with atypical neuroleptics. Conclusions. Several further perspectives of estrogen-studies in schizophrenic women are discussed.

        Key words: schizophrenia, menstrual cycle, estrogen.