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A long-lasting injection;

Releases the hormone progestogen, which stops ovulation, thickens cervical mucus, and thins the lining of the uterus to prevent pregnancy.

99% effective if used as directed.


  • Lasts for 13 weeks
  • Don’t have to think about contraception for as long as it lasts
  • Not affected by diarrhoea and vomiting, as not absorbed by the tummy
  • May make periods lighter and less painful
  • Can self-inject once assessed – meaning only one clinic visit per year


  • Bleeding may stop or become irregular or heavier
  • Fertility may take up to 12 months to return after stopping the injection
  • No protection against STIs
  • Some people gain weight
  • Can cause slight thinning of the bones mostly in younger people or women over 50 (usually recovers once the injection is stopped)


  • Injection cannot be removed from the body, so any side effects may continue for as long as the injection lasts.
  • Important to have your next injection at the right time.
  • Not affected by other medicines.

Further information: