The contraceptive injection – Everything you need to know

Reviewed: October 4, 2021
The injection is different from any other contraceptive, and here's why

The contraceptive injection is a little different from all the other contraceptives. This contraceptive does not need to be inserted into the vagina or taken orally, meaning in terms of convenience, it’s already a winner.

If you’re done with having to remember to take the pill every day and also cringe at the thought of the coil, then this convenient contraceptive could be the answer to all of your prayers!

What is the contraceptive injection and how long does it last?

The contraceptive injection, also just known as the injection, is injected into your body every 2-3 months. Like most contraceptives, there are different varieties of this; Depo-Provera is the most commonly given in the UK and lasts for 13 weeks. Noristerat is another option, however, it only lasts 8 weeks. A more recent injection is Sayana Press which also lasts for 13 weeks but as it is a newer type of injection, it’s not available in all clinics or GP’s surgeries just yet.

How effective is the contraceptive injection?

If used correctly, the injection is 99% effective.

How does the contraceptive injection work?

The injection steadily releases the hormone progestogen into your bloodstream. It prevents pregnancy in three ways – by stopping ovulation, by making the fluid in your cervix thicker (which makes it more difficult for sperm to enter the womb), and by preventing the lining of your womb thickening enough for an embryo to grow in it.

How do I get started on the contraceptive injection?

Your doctor or nurse will first do some tests to make sure you are able to have the injection. They will check your medical history, make sure you’re not pregnant and take your blood pressure. You can have the injection at any time during your period cycle. If you have it within the first five days of your cycle, you will be protected from pregnancy straight away.  Any other time in your cycle and you’ll need to use condoms for seven days. You can have the injection straight after giving birth or having an abortion or miscarriage. If you’re breastfeeding, the injection will usually be given six weeks after giving birth.

You will be given the injection as you would a standard jab.

  • Depo-Provera can also sometimes be given in the arm
  • Noristerat is a thicker solution so you may find the injection is slightly more painful when it’s given
  • Sayana Press is injected beneath the skin at the front of the thigh or abdomen. It’s possible for you to be taught how to inject Sayana Press yourself at home but not all GPs and clinics currently offer this

The injection can’t be removed from your body. If you have any side effects, you have to be prepared for them to continue during the eight or 13 week period, and for some time afterward. The most common side effects are a change in bleeding (68% of Lowdown users stated a complete stop in their periods), weight gain (stated by 42% of Lowdown users), and loss of sex drive (stated by 50% of Lowdown users). Like any other hormonal-based contraceptive, this can also cause headaches and mood swings, however these normally only occur during the first couple of months, while your body is adjusting to the change in hormones.

After the injection has been given, you will only need to go back to your doctor or nurse if you have any problems or when you need a new injection. If you are using the Sayana Press (which you injected yourself at home), you only have to go back to the clinic annually because you will be given a year’s supply.

How do I stop the contraceptive injection?

Before you get the injection, it’s good to know that it can take between several months to a year for the hormones to leave your system and for your fertility to return to normal. To stop, all you need to do is not have your next injection – if you don’t want to get pregnant then you should use another method of contraception from the day that your next injection would have been due.

Contraceptive injection pros and cons


  • A contraceptive that doesn’t need to be taken daily
  • It’s not affected by other medicines
  • Doesn’t interrupt sex
  • Safe to use whilst breastfeeding


  • The injection can cause thinning on the bones as it affects your natural estrogen levels. The NHS advises that bone thinning isn’t normally a problem for most injection users and more so for users that already have risk factors of osteoporosis
  • In very rare cases you can have an allergic reaction to the injection
  • Some medicines and antibiotics (rifampicin and rifabutin, St John’s wort and anti-epilepsy drugs) make the injection less effective
  • With any combined type of hormonal contraception, there is a slightly increased risk of developing blood clots in your veins and arteries

Who should take it?

  • Females that cannot use contraception that contains oestrogen
  • Females that cannot remember to take a pill every day
  • Females that are breastfeeding
  • Females that want their periods to stop

Who shouldn’t take it?

  • Females that want their fertility to return to normal immediately after finishing on a contraceptive
  • Females that want protection from STIs
  • Females that don’t want their periods to change
  • Females that are at risk of osteoporosis

Where can I get it?

You can get the injection for free, even if you’re under 16, from contraception clinics, sexual health or genitourinary medicine clinics and GP surgeries.

Sayana Press is a new form of Depo-Provera and is available in some clinics. It’s very similar to Depo-Provera in the way it works and the effects it can have on your body. But you’ll be taught how to give yourself the injection, rather than having a doctor or nurse give it to you.

This guide was brought to you by The Lowdown. We are the world’s first contraception review platform, providing real-life experiences from thousands of reviews collected from our community of men and women.

Why not leave us a review of your contraceptive experience? Whether you’ve got good things to say about the Mirena coil or had trouble with implant removal, we want to hear about it! Tell us about your experience and help people around the world find the right method for them.