• Releases small amounts of progestin (a hormone) into the bloodstream.
• Hormone stops ovaries from releasing eggs.
• Thickens mucus at cervix, which prevents sperm from entering the uterus.
  
   

• Injection in arm or buttocks must be given every 12 weeks by a clinician.
• Depo can be given without a pelvic exam after a medical history and blood pressure are taken.
  
   

• Easy to use.
• Doesn't interrupt sex.
• Extremely effective.
• May be used by some women who are unable to use the Pill.
• Decreases or stops menstrual periods.
  
   

• Requires an injection.
• Can take up to 18 months to get pregnant after the last injection.
• No protection against STIs/HIV.
• Other possible side effects: Headaches, mood changes, weight gain or loss, sore breasts or nausea.
• Side effects may take up to 1 year to go away.
  

Effectiveness: 99.7%

More information on Depo-Provera.