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What is the contraceptive injection?

The contraceptive injection contains a progestogen hormone. This is injected into a muscle (Depo-Provera® injection) or the skin (Sayana Press® injection) and is released very slowly into your body. It will protect you from pregnancy for 13 weeks.
The main way the injection works is to stop your ovaries releasing an egg (ovulation), thickening of the cervical mucus to prevent sperm reaching an egg and thinning of the lining of the womb to prevent a fertilised egg implanting.

You can get the injection free of charge from your GP or at Sandyford. All our clinics stock injections.

The doctor or nurse will consider your medical history to make sure you can have an injection and tell you about any possible side-effects. If you have any questions ask the doctor or nurse.

The injection protects you from pregnancy but not sexually transmitted infections. You must also use condoms to help protect against infections.

You do not need to have a vaginal examination or a cervical screening test to have a contraceptive injection.

How effective is it?

Contraceptive use can either be perfect (always correct) or typical (more accurate, as it’s sometimes difficult to use contraception correctly every time). 
With typical use of the combined pill, approximately 3 in 100 people become pregnant within the first year of use

What makes it less effective?

  • If you do not have your next injection on time.
  • Some medications including some herbal medicines can make your contraception less effective. Always tell your doctor, dentist or chemist if using the contraception injection.

What are the advantages?

  • You don't have to think about contraception for as long as the injection lasts.
  • It doesn't interrupt sex.
  • You can use if you are breastfeeding.
  • They give you some protection against cancer of the uterus.
  • They are useful if you cannot take oestrogens, like those in the combined pill.
  • It may reduce heavy painful periods and help with premenstrual syndrome.

Are there any disadvantages?

  • There may be changes in your period pattern: most commonly your periods become lighter and often disappear. Sometimes there can be extra bleeding or irregular spotting. This may be irritating but it is not harmful.
  • Other possible side effects can include: headaches, acne, appetite or mood changes, tender breasts or bloating.
  • Some women might put on a small amount of extra weight when they use the injection.
  • It may take several months for your period and fertility to return to normal after you stop the injections.
  • The injection works for 13 weeks. It cannot be removed from your body, so if you have any side effects, they may continue during this time and for some time afterwards.
  • Contraceptive injections do not protect you against sexually transmitted infections.

 Only condoms can provide protection against most infections.

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