Clinical experience of a combined oral contraceptive with very low dose ethinyl estradiol
Akerlund, M.
Acta Obstetricia et Gynecologica Scandinavica. Suppl 164: 63-65
1997
ISSN/ISBN: 0300-8835 PMID: 9225641 Document Number: 474199
In response to concerns about a possible thromboembolism risk, the ethinyl estradiol dose in oral contraceptives (OCs) has been further decreased. This study compared the effectiveness and metabolic effects of combined OCs containing 150 mcg of desogestrel and either 20 or 30 mcg of ethinyl estradiol. 1000 Swedish women requesting an OC were randomly assigned to receive either the 150/20 or 150/30 formulation, with follow-up visits scheduled 3, 6, and 12 months after OC initiation. The only 2 pregnancies attributable to method failure occurred in the 150/30 group. Although bleeding irregularities were more common in the 150/20 group, this incidence steadily decreased over the 12-month study period. Overall, bleeding irregularities were experienced by 9.9% of the 500 women in the 150/20 group and 6.0% of the 500 in the 150/30 group. The total cholesterol level increased significantly in the 150/30 mcg group but not in the lower-dose group. Low density lipoprotein cholesterol decreased only among 150/20 OC users. Total triglycerides increased more in users of the 30 mcg pill. Both pills reduced free testosterone levels substantially, but to the same extent. The small percentage of women who experience irregular bleeding with the lowest-dose OC are likely to accept this discomfort in exchange for its potentially improved safety profile.