This article consists of 5 case reports of women who developed abnormal glucose tolerance, glycosemia and/or glucosuria while taking oral contraceptives, and a review of the literature on diabetogenic effects of 3 estrogen and 7 progestagens commonly used as contraceptives, as well as predisposing factors for this disorder. The 5 women all improved after stopping pills. There are reports that diethylstilbestrol decreases glucose tolerance, that ethinyl estradiol augments insulinemia and decreases iv glucose uptake. 2 studies reported that mestranol decreased glucose tolerance in 50 and 57% of women. Mestranol has been said to have no diabetogenic effects when given as a combined pill, and to ameliorate maturity-onset diabetes. Progesterone, the 19-nor-testosterone derivatives norethisterone and norethisterone enanthate, and ethynodiol diacetate have no effect. 17-alpha-hydroxy-progesterone caproate, medroxyprogesterone acetate and chlormadinone have received contradictory reports. Megestrol acetate has been been known to normalize diabetic symptoms. Family history of diabetes or glycosuria of pregnancy, large infants or stillbirths predispose to diabetes during oral contraception, but age, weight parity and duration of oral contraception have received contradictory reports. Diabetes developing during oral contraception is usually reversible.