Clinical and endocrine effects of long-term hormonal contraception.

Clinical effectiveness and side effects of a biphasic oral hormonal contraceptive preparation (levonorgestrel /LNG/ 10 X 0.05 mg+ + 11 X 0.125 mg, ethinyl oestradiol /EO/ 21 X 0.05 mg) were compared with the effect of a classical high fixed dose combination pill (LNG 21 X 0.25 mg, EO 21 X 0.05 mg). The biphasic pill was used by 121 women during 1844 cycles, while the fixed dose pill was used by 142 women during 1940 cycles. In the comparison with the life table method, termination of pill use for medical reasons and loss to follow up proved to be significantly different in favour of the biphasic pill.