The effects of a "low-estrogen" oral contraceptive on carbohydrate metabolism during six months of treatment: a preliminary report of blood glucose and plasma insulin values.

A prospective study of carbohydrate metabolism was carried out on seven women by using an oral glucose tolerance stimulation test and measuring blood glucose and plasma insulin values over a 3-hour time period. The test was performed before and after 6 months of treatment with a "low-estrogen" oral contraceptive containing 0.4 mg of norethindrone and 35 micrograms of ethinylestradiol. There was no change in the weight or diastolic blood pressure of the women, but there was a slight elevation of the systolic blood pressure with treatment. There was no significant change in the plasma insulin values or in four of five blood glucose values. The 1-hour blood glucose value was significantly lower after 6 months of treatment. These results suggest that the "low-estrogen" oral contraceptives may reduce the secondary effects on carbohydrate metabolism seen with regular oral contraceptives.