OBJECTIVE The purpose was to evaluate the metabolic effects of Mircette (brand of desogestrel/ethinyl estradiol and ethinyl estradiol), a low-estrogen, desogestrel-containing oral contraceptive. METHODS Women taking Mircette were evaluated to determine its effects on lipid profiles (n = 74), carbohydrate metabolism (n = 25), and endocrine parameters (n = 53). RESULTS During cycles 3 and 6 of Mircette treatment, changes from baseline included mean increases in serum triglycerides and very low-density lipoprotein cholesterol ranging between 50% and 60%. Smaller mean increases were observed at these time points in high-density lipoprotein cholesterol subfraction 2 (range between 17% and 25%), total cholesterol (<10%), high-density lipoprotein cholesterol (range between 10% and 15%), and high-density lipoprotein cholesterol subfraction 3 (range between 9% and 13%), with only nominal changes (<6%) in low-density lipoprotein cholesterol and lipoprotein. Patients receiving Mircette showed no mean changes in fasting plasma glucose or serum insulin levels but did have modest increases in glucose and insulin levels after a glucose challenge. Mircette treatment suppressed follicle-stimulating hormone, luteinizing hormone, 17beta-estradiol, and progesterone to levels consistent with inhibition of ovulation and increased concentrations of thyroid- and cortisol-binding globulins. CONCLUSIONS Overall, Mircette treatment was associated with expected effects on the pituitary-ovarian axis, triglycerides, and serum binding proteins; a modest decline in glucose tolerance; and a favorable effect on lipid profiles as a result of increases in total high-density lipoprotein cholesterol and high-density lipoprotein cholesterol subfraction 2 in the absence of changes in total cholesterol or low-density lipoprotein cholesterol.