This study aimed to assess short-term (12 weeks) and long-term (12 months) gender differences in the outcomes of patients experiencing an episode of mania in the course of bipolar disorder. European Mania in Bipolar Longitudinal Evaluation of Medication was a 2-year, prospective, observational study of the outcomes of patients with a manic or mixed episode conducted in 14 European countries. Data were collected during the acute phase (12 weeks) and during a follow-up period (up to 12 months). Analyses were carried out in the subgroup of patients identified with a pure manic episode at baseline. Kaplan-Meier survival analysis estimated time to first occurrence of mania improvement, worsening, recovery and depressive episode, and Cox's proportional hazards models were used to analyse factors associated with these outcomes. Overall, 2,485 patients (46.6% men, 53.4% women) were included in the analysis. Frequency of substance abuse was higher in men than women. No significant gender differences were found in the severity of manic symptoms at baseline. There were no gender differences in assessment of mania improvement, worsening or recovery over 12 weeks, but more women than men showed mania improvement over 12 months (95.4% vs. 89.2%; p < 0.01). Significantly more women developed a depressive episode over 12 weeks (14.9% vs. 9.7%; p < 0.01) and over 12 months (27.7% vs. 21.5%; p < 0.001). In conclusion, the results show that there are small gender differences in the course of patients experiencing a pure manic episode. Women had a faster time to mania improvement and a higher risk of developing a depressive episode during the 12-month follow-up period.