Cyclic changes in serum cholesterol and lipoproteins following different doses of combined postmenopausal hormone replacement therapy.

Cyclic changes in lipoproteins after sequential oestrogen-progestogen therapy were studied in a group of healthy postmenopausal women treated with three different hormone doses, and followed up for two consecutive cycles by twice weekly examinations (a total of 17 examinations). There was a significant rise in high density lipoprotein (HDL) cholesterol and a significant fall in low density lipoprotein (LDL) cholesterol closely related to the dose of the oestrogen component. Addition of the progestogen, 1 mg of norethisterone acetate, decreased the oestrogen-induced rise in HDL, but HDL levels remained higher than initial values in the high-dose (4 mg) and medium dose (2 mg) groups. The average increases in HDL cholesterol were 13%, 9% and 2% in the high-dose, medium-dose and low-dose (1 mg) groups, respectively, and the corresponding mean decreases in LDL cholesterol were 18%, 15% and 10% respectively. We conclude that postmenopausal treatment with sequentially combined oestrogen-progestogen has no adverse effects on the lipoprotein status.