The Injection

The Injection

How Does The Injection Work?

The contraceptive injection releases the hormone progestogen into your blood to prevent pregnancy. It lasts for 8 or 13 weeks, depending on what one you are given.

What To Expect At Your Appointment?

The Injection needs to be fitted by a trained nurse or doctor although there is one type you can administer at home.

During the appointment, you can expect the nurse to ask you a few questions and check which injection is suitable for you and also check your weight and blood pressure.

Depending on the type of injection, it will either be injected into the bum, thigh, tummy or arm.

If you’re given the injection during the first 5 days of your period you will be protected against pregnancy straight away.

If you have the injection on any other day of your cycle you will not be protected for the first 7 days, so you will need to use another method of contraception, like condoms.


✅ The injection works for 8 or 13 weeks (depending upon which one is used)
✅ It may reduce heavy periods and period pain
✅ It can be used by some women who cannot use oestrogen
✅ The injection is not affected by being ill or medication
✅ Using the self-injection may mean only going to your GP once a year


❌ It does not protect against STIs
❌It’s common to experience temporary side effects during the first few months, like headaches, nausea, breast tenderness and mood swings
❌ Periods may be irregular, heavier, and longer or they may stop altogether
❌ It can cause slight thinning of the bones by reducing bone mineral density (this usually recovers once the injections stop)
❌ It may take a while for your periods to return to normal when you stop having the injection
❌ Some women may put on weight
❌ There can be a very small risk of infection at the site of the injection


⚡ I am not a health professional. I am qualified in RSE but I am not a doctor. Content for this page has been drawn from the NHS website and Please head over to these great sites for more details.

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