Objective: To evaluate and compare the contraceptive efficacy, bleeding pattern, side effects and other positive effects of a combined oral contraceptive (COC) containing drospirenone (DRSP) [Yasmin (R)] with those of a COC containing desogestrel (DSG) in healthy Chinese women. Methods: This was a randomized, open-label, controlled, multicentre study of 768 healthy Chinese women requiring contraception. The subjects were randomized to ethinylestradiol (EE) 30 mu g/DRSP 3 mg (n = 573) or EE 30 mu g/DSG 150 mu g (n = 195), at a ratio of 3 : 1. Each individual was treated for 13 cycles. Further visits were required at cycle 4, cycle 7, cycle 10 and cycle 13 of treatment. Weight, height and body mass index were evaluated at each visit. The Menstrual Distress Questionnaire (MDQ) was administered at baseline, visit 3 (cycle 7) and visit 5 (after cycle 13). Results: Baseline characteristics were similar between the two groups (p > 0.05). The Pearl Index (method failure) for EE/DRSP was 0.208 per 100 women-years, which was lower than that for EE/DSG (0.601 per 100 women-years). There were no significant differences between the treatment groups with regard to bleeding patterns. According to the MDQ subscale, improvements in water retention and increases in appetite during the intermenstrual period and in water retention and general well-being during the menstrual period in the EE/DRSP group (-0.297, -0.057, 0.033 and 0.150, respectively) were significantly improved compared with the EE/DSG group (-0.108, 0.023, 0.231 and -0.023, respectively) [all p < 0.05]. Other values that improved in both groups, particularly improvement in breast pain and tenderness and skin condition, were more evident in the EE/DRSP group (18.0%, 89/494; 12.6%, 62/494) than in the EE/DSG group (11.3%, 19/168; 5.4%, 9/168). Mean weight increased in the EE/DSG group (0.57 kg) while there was a significant decrease in mean weight (-0.28 kg) in the EE/DRSP group (p<0.01). Conclusions: Both EE/DRSP and EE/DSG have good contraceptive efficacy and a comparable bleeding pattern. EE/DRSP had a more favourable effect on weight and premenstrual symptoms than EE/DSG.