Some studies suggest seasonality of suicide attempts in females, but not males. Only few studies investigated whether gender differences in seasonality of suicide attempts reflect gender differences in the choice of method, with inconsistent results.

To analyze the association of gender with seasonality in suicide attempts by persons living in two Northern Bavarian regions (city of Nuremberg and region of Wuerzburg) between 2000 and 2004.

The sample consisted of 2269 suicide attempters (882 males and 1387 females). The overall seasonality was assessed using the chi2 test for multinomials. Moreover, the ratio of observed to expected number of suicide attempts (OER) with 95% confidence intervals within each season was calculated.

Overall distribution of suicide attempts differed significantly between seasons for women (chi2 = 9.19; df = 3; p = 0.03), but not for men. Female suicide attempts showed a trough in the spring (OER = 0.9; 95% C.I. = 0.8 – 1.0) which was restricted to female low-risk suicide attempts (OER = 0.87; 95% C.I. = 0.77 – 0.98). No seasonality was found for men. Seasonality of high-risk methods was more pronounced than that of low-risk methods; however, no significant gender differences were found.

The overall distribution of the sub-types of suicidal acts (parasuicidal gestures, suicidal pauses, suicide attempts in the strict sense) showed seasonality neither for males nor for females.

Whereas seasonality was absent in male suicide attempters, the frequency of low-risk suicide attempts in females was 13.1% lower than expected in the spring.