Pharmacology: Medroxyprogesterone Acetate prevents follicular maturation, producing long term anovulation in the reproductive-aged woman. Andalan 150 mg administered intramuscularly every three months acts as a contraceptive for women. For the best result, the first dose must be given during the first 5 days of the normal menstrual cycle or in the immediate postpartum period. During treatment, the normal menstrual cycle is replaced by periods of irregular and unpredictable vaginal bleeding, spotting or complete amenorrhea. The time period of bleeding and/or spotting in the majority of women is 7 days or less in one month. Bleeding tends to decrease with continued injection. Sometimes there will be excessive bleeding or the bleeding may last for longer period, especially early in the course of treatment and this can usually be controlled by giving estrogen orally or by intramuscular injection with the dosage equal to 0.05-0.1 mg ethinyl estradiol daily for 7-12 days. Restoration of menstrual cycle to normal may need 5-28 months after the last injection of Andalan.