Objectives: Poor cycle control and tolerability can be reasons for irregular pill intake. This study compared the tolerability of two low-dose oral contraceptives and their effect on cycle control.

Methods: In this open, group-comparative, randomized multicenter trial in Germany and the Netherlands, women received either 20 microg ethinylestradiol plus 150 microg desogestrel (20EE/DSG; n = 500) or 20 microg ethinylestradiol plus 100 microg levonorgestrel (20EE/LNG; n = 498) for six treatment cycles. Cycle control, dysmenorrhea and premenstrual syndrome (PMS) were assessed using diary cards. Tolerability was assessed using the self-administered questionnaires Psychological General Well-Being Index (PGWBI) and the Profile of Mood States (POMS). Acne was assessed by objective (acne counts) and subjective (no, moderate, mild, severe) acne scoring of the facial area at baseline and treatment cycles 1, 3 and 6.

Results: A total of 404 (78.1%) and 384 (75.3%) women in the 20EE/DSG and 20EE/LNG groups, respectively, completed the trial. The occurrence rate of irregular bleeding and spotting was statistically significantly higher with 20EE/LNG than with 20EE/DSG (0.18 vs. 0.13; p < 0.05). The mean number of bleeding-spotting days per cycle was statistically significantly higher with 20EE/LNG than with 20EE/DSG (0.63 vs. 0.48; p < 0.05). Early withdrawal bleeding was more frequent with 20EE/LNG (0.15 vs. 0.08; p < 0.005), whereas continued withdrawal bleeding was more frequent with 20EE/DSG (0.32 vs. 0.45; p < 0.001); absence of withdrawal bleeding was comparable (0.06 vs. 0.04, respectively). Thirteen subjects in the 20EE/LNG group and three in the 20EE/DSG group discontinued due to unacceptable bleeding (p < 0.05). Dysmenorrhea and PMS decreased comparably in both groups. There were no differences between groups for the mean total scores of PGWBI or POMS at all time-points. Fewer acne lesions were counted with 20EE/DSG vs. 20EE/LNG after six cycles (p < 0.05). The subjective acne scores supported this finding.

Conclusions: 20EE/DSG provided better cycle control than 20EE/LNG with less treatment discontinuation due to unacceptable bleeding. There were no apparent differences between the two groups regarding tolerability and quality of life. There was less acne with 20EE/DSG.