Intravenous glucose tolerance tests were carried out in women taking two types of oestrogen‐progestogen combination oral contraceptives. Each subject had the test done on day 18‐21 in a control cycle before the medication was started and three consecutive cycles during administration of the drug. Fasting blood glucose levels and K values showed no significant changes with combination of megesterol acetate (4 mgm.) with 0.05 mgm. of ethinyl oestradiol. A significant decline in glucose tolerance was observed by the change in K values during all the three cycles of medication with combination of Lynestrenol 2.5 mgms. with 0.075 mgm. of mestranol. Tests repeated after 2 months after stoppage of medication in five subjects showed that blood sugar levels and K values had returned to pretreatment lev