Intravenous glucose tolerance tests were conducted in 3 groups of women on two different occasions during a menstrual cycle—on Day 14 (estrogen peak) and on Day 24 (progesterone dominance). The first group took no medication, the second group received a sequential-type contraceptive compound, and a third group was given a progestational-type oral contraceptive preparation. Only the second group showed a slightly reduced glucose tolerance in the first test (Day 14); but it was not statistically significant It was concluded that endogenous and exogenous estrogen changes during the menstrual cycle in women had no significant effect on carbohydrate metabolism.