SEASON OF BIRTH AND BIPOLAR DISORDERS - A REVIEW AND A PRELIMINARY-STUDY

The authors have revieweed the few literature dealing with the season of birth in bipolar disorder. A retrospective study of 294 patients pr esenting bipolar disorder (DSM III-R criteria) was undertaken ; its ai m was to assess the hypotheses of an excess of birth in winter among t hese patients. Our data show 1) a trend to an excess of winter birth a mong bipolars as a whole ; 2) a significant excess in bipolar type I ; 3) no difference in bipolar type II. Methodological caveats are discu ssed as well as possible implications of these researches in the presu me continuum between affective disorder and schizophrenia.