Long-term effects of injection Depo-Provera (depo-medroxyprogesterone acetate) on carbohydrate and lipid metabolism were studied in 157 women who were treated continuously for a mean duration of 43.3 months. The patients were matched with 162 controls for race, age, parity and height. Glucose tolerance was impaired with higher intolerance at longer duration. Glucose areas were significantly higher at 48 and 60 months of injection. Insulin levels were also significantly decreased at 30 minutes and increased at 150 minutes but the area was normal. Triglycerides were initially decreased, being significant at 36 months (p less than 0.001) and returned to normal at 60 months while cholesterols were significantly higher at 24 and 36 months (p less than 0.05) and 60 months (p less than 0.001). In view of these findings, Depo-Provera may have an advantage over oral pills on a short term basis as there are less alterations in carbohydrate and lipid metabolism.