Medroxyprogesterone acetate (MPA), a potent progestagen, is used as a very efficient contraceptive agent. The method of administration is by a threemonthly or sixmonthly intramuscular injection. The method is particularly convenient when the desired number of children has been reached. Fertility is sometimes reestablished only slowly after stopping the injections. The main side effects are linked to endometrial atrophy (blood loss, amenorrhoea). Other side effects are infrequent and subjective. A controversy has risen over the product, by reference to its effects on beagle dogs. We have reviewed the literature. We also present the characteristics of 313 patients treated during (all together) 8,000 months. These patients belong to a rather poor sample of the population (amongst them many immigrant women), aged about 30, with above average pregnancy and parity rates. We also studied, in 31 patients, serum levels of glucose and lipids, and haemostasis. Side effects and reasons for discontinuing the drug are reported. The Pearl index was 0,75% women-years. There was no average effect on weight, blood tension, glycemia. Triglycerides increased slightly, and there was a discreet activation of coagulation with inhibition of the fibrinolytic activity, but without clinical consequences. We conclude that we can go on prescribing the drug, in view of our study and after reviewing the literature.