Mechanism of Hypertriglyceridaemia Associated with Contraceptive Steroids

Abstract

Plasma free fatty acid and triglyceride turnover rates were determined in thirty-five premenopausal adult healthy females. Eleven subjects were studied while taking a combined oestrogen-progestagen contraceptive preparation, seven women were taking either progesterone or megestrol alone, five women were taking an oestrogen preparation alone, and fifteen women served as controls. The plasma free fatty acid concentration and turnover rate were not affected by any of these steroids. The triglyceride concentration and turnover rate were increased in women taking either the combined preparation, or oestrogen alone. The intake of combined preparation was associated with increased clearance of both endogenous and exogenous triglycerides, though the post heparin plasma lipolytic activity was not altered. Women using either progesterone or megestrol showed a decrease in serum triglyceride concentration associated with both increased triglyceride clearance and increased activity of post-heparin plasma lipolytic activity. In this group, the triglyceride turnover rate was not affected. Women taking oestrogen alone had normal rates of clearance of plasma triglycerides. These results suggest that the increase in triglyceride turnover is the result of the oestrogenic component while the increase in triglyceride clearance is the net effect of the progestagen moiety. The changes in triglyceride turnover rate were significantly conelated with the duration of administration and the peak plasma insulin response to an oral glucose load.