A prospective randomized study comparing the clinical effects of a norethisterone and a levonorgestrel containing low dose oestrogen oral contraceptive pills.

The two types of low dose oral contraceptives one containing levonorgestrel the other containing norethisterone have been compared in a randomized prospective study. We have found that cycle control was much poorer with the norethisterone pill and would therefore recommend that if the norethisterone-containing pill needs to be prescribed then either the 1 mg or the 'synphasic' preparation should be considered.