OBJECTIVE: To investigate whether childhood sociodemographic factors and parental psychopathology affect suicide risk differently in men and women. METHOD: Cox regressions were used to calculate interaction effects of gender for childhood and parental risk factors for 8815 suicides (27% women) in a national cohort of 2.47 million people born between 1946 and 1968. RESULTS: Low parental socioeconomic status increased suicide risk only for men, hazard ratio (HR) = 1.22 (P = 0.003 for gender interaction), while living in a metropolitan area increased the risk only for women, HR = 1.42 (P