Several studies show that the season of birth of suicide victims does not follow a random distribution.

To examine season of birth, of a sample of suicide victims from Greece. We collected data from the Athens Department of Forensic Medicine, the largest in Greece, referring to the suicide victims of a 2-year period (November 2007-October 2009).

Date of birth was available for 296 out of a total of 335 suicide victims; 30% were born in winter, 30.5% in spring, 19.3% in summer & 20.3% in autumn. Relatively more were born in January (15.2%) & May (12.2%), fewer in June (4.1%) & November (5.1%). Our findings are in accordance with most of the relevant literature: It has been also shown that a seasonal distribution is associated with the high sensitivity of the CNS to environmental exposure in utero, infections, hormonal changes, maternal diet, photoperiod, temperature & weather conditions. Winter-borns more frequently present modifications in the behavioral expression of dopaminergic genetic polymorphisms that could predispose to impulsive & risky, as well as sensation seeking behaviors, later in life. Furthermore, low serotonin turnover at birth has been observed in those born between February & April; it is well-known that similar findings have been documented in adult suicidal behavior too.

Risk of completed suicide seems to be higher for those born during winter & spring. More research is needed in order to clarify if season-month of birth should be included in the future assessment of suicide risk.