Effect of low-dose oral contraceptives on lipoproteins and lipolytic enzymes: Differences between two commonly used preparations

Changes in circulating lipoproteins which may be related to the risk for atherosclerotic vascular disease were studied in a control group and in 2 groups of 24 or 26 women using different preparations of low-dose oral contraceptives (OCs) for 3 months. 1 preparation contained 150 mcg levonorgestrel and 30 mcg ethinyl estradiol (Stediril-d 150/30); the other contained 750 mcg lynestrenol and 37.5 mcg ethinyl estradiol (Ministat). No significant changes were found with either of the preparations in serum cholesterol or high density lipoprotein cholesterol (HDL-C) levels. Apolipoprotein A-II levels increased during Ministat treatment from 50.4 to 61.4 mg/dl and during Stediril-d 150/30 treatment from 52.7 to 58.9 mg/dl (both P0.001). These changes differed significantly from each other (P0.01). Apolipoprotein A-I levels increased significantly during use of Ministat only. Apolipoprotein B in low density lipoprotein increased by about 20% (P0.001) in both groups. Post-heparin lipoprotein lipase activity did not change but hepatic lipase activity decreased to the same extent in both groups (P0.001). Reductions in post-heparin lipase activity were not correlated with increases in HDL-C. (authors)