Carbohydrate metabolism during hormonal substitution therapy

Oestrogens and progestogens are known to influence glucose tolerance. Impairment of glucose tolerance is seen in particular among users of progestogens with androgenic properties. Dydrogesterone is frequently used as the progestogen adjunct during oestrogen substitution therapy for the management of climacteric complaints in post-menopausal women. However, no detailed data have been published concerning its effects on carbohydrate metabolism. In this study, 20 healthy post-menopausal women received equine oestrogens at a dose of 0.625 mg/day for 2 mth, following which dydrogesterone was added cyclically (20 mg/day for 12 days/mth) over a period of 6 mth. Oral glucose tolerance tests were performed before and after each treatment regimen. In relation to the concentrations observed after oestrogen was given alone, dydrogesterone induced only a small increase in blood insulin values which was not statistically significant. The effect was similar to that produced by endogenous progesterone, which is known to be of no clinical significance.