Hormonal Methods: 5: A single intramuscular injection of depot medroxyprogesterone acetate or DMPA (DepoProvera), a progesterone given every 12 weeks, inhibits ovulation, alters the endometrium, and thickens the cervical mucus so sperm progress is difficult. -effectiveness rate of this method is almost 100% -made deep into a major muscle (buttocks, deltoid, or thigh) before the fifth day after the beginning of a menstrual flow. -do not massage the injection site after administration -can be used during breastfeeding, although women should wait 6 weeks after birth for for first injection. Advantages: -decreases in ectopic pregnancy, endometrial cancer, endometriosis, and, for unknown reasons, the frequency of sickle cell crises -must return to a healthcare provider for a new injection every 12 wks to remain stable.