Season of Birth of Psychotic Patients

Abstract

Seasonal distribution of births of 9, 868 schizophrenic patients and 1, 795 manic-depressive patients in Tokyo born during the period 1841-1960 and treated at two hospitals during the period 1879-1976 was investigated by year of birth and sex.
Both schizophrenic and manic-depressive birth distributions showed deviations from the control. How the distributions deviated was different by year of birth and sex of the patients. The deviations per se, could be seen in both male and female patients.
Considering the fact that birth seasonality of psychotic patients varied by period of birth and sometimes by sex, it is suspected that those“endogenous”mental diseases may be prepared by plural exogenous seasonal epidemic factors which act on fetal or neonatal stages and some of which may interact with sex difference.