Effects of levonorgestrel and desogestrel in low-dose oral contraceptive combinations on serum lipids, apolipoproteins A-I and B and glycosylated proteins.

Fasting serum lipids, apolipoproteins and glycosylated serum proteins were studied in 20 women before, after three months of treatment and two months after termination of treatment with oral contraceptives containing 30 micrograms ethinyloestradiol (EE) plus 150 micrograms levonorgestrel or desogestrel. Levonorgestrel + EE induced significant increases in total triglycerides (48%), apoB (19%) and the ratio apoB/apoA-I (18%) and no significant changes in HDL-cholesterol (8% decrease), apoA-I, % HDL-cholesterol, total cholesterol and serum glycosylated proteins. Desogestrel + EE induced significant increases in HDL-cholesterol (12%), % HDL-cholesterol (15%), triglycerides (35%) and apoA-I (20%), no changes in total cholesterol, apoB and glycosylated serum proteins and a significant decrease in the ratio apoB/apoA-I (17%). Two months after termination of treatment the values for all parameters for both preparations were similar to those observed before treatment. The differences between the effects of the two preparations on the parameters HDL-cholesterol, % HDL-cholesterol, apoA-I, apoB and the ratio apoB/apoA-I were statistically significant and can be explained by a difference in the intrinsic androgenicity of the two progestagens.