The effect of combination and low dose progestogen oral contraceptives on serum lipids.

Fasting serum triglyceride, free fatty acid, phospholipid, and cholesterol levels were determined in women who were taking either combination or low dose progestogen oral contraceptives. The contraceptives used were: ethynodiol diacetate and ethynyl estradiol; norgestrel and ethynyl estradiol; norgestrel; and megestrol acetate. Serum lipids significantly increased in women taking combination pills. They significantly decreased in patients taking norgestrel, while they remained almost unchanged in patients taking megestrol acetate. This decrease varied with the type of progestogen used in continuous low dosage therapy. The confusion when interpreting the results from different reports on the effects of oral contraceptives on serum lipids will be reduced if proper attention is given to the types of steroid used.