How Do They Work?


The IUD coil or ‘copper coil’ is a little bit of plastic shaped like a T, that sits in the uterus. It is made from copper which is toxic to the sperm and also stops the egg from implanting into the womb.

It can stay in your body for 5-10 years or until you would like it taken out.

It can also be fitted as emergency contraception as it works instantly.


The IUS could or ‘hormonal coil’ is is a little bit of plastic shaped like a T, that sits in the uterus. It is contains the hormone progestogen, which thickens the mucus around the cervix, making it harder for the sperm to get through. On top of this, it makes the lining of the womb thinner so that a fertilised egg cannot implant.

Some people stop ovulating (ovaries release an egg) and bleeding on this coil, however most continue to ovulate.

What To Expect At Your Appointment 


Both the IUD and IUS need to be fitted by a trained nurse or doctor.

During the appointment you can expect the nurse to ask you a few questions and to check your vagina is suitable for insertion and that you don’t have an infection down there – if so you will be given some antibiotics.

The actual fitting of the IUS/IUD should take no longer than 5 minutes. You can sometimes be given some painkillers or local anaesthetic to help with the pain, although some people find it just a little uncomfortable.

You will be asked to lay on the bed with your bottom half of your clothing removed. You will then open your legs and bend your knees and they will insert a speculum inside your the vagina and insert the coil.

The IUS is often used to help with endometriosis pain and the IUD can be used as an emergency contraception as it works instantly.

Once the coil is fitted you will feel some period contraction like pain as your body is trying to remove the ‘foreign object’ along with some light bleeding. However, this should subside within a few days.

You should go back to the or doctor or nurse if you have severe or prolonged stomach pains, especially if you feel unwell, hot and clammy or heavy vaginal bleeding with or without clot.

Removal is the same as insertion but in reverse but it should be less uncomfortable!


✅ Nothing to remember to take/put on.
✅ Prevents pregnancy for up to 3 or 5 years depending on the brand of IUS.
✅ Your periods may be lighter, shorter, or they may even stop completely
✅ Your fertility will return to normal after the IUS has been removed
✅ There is no evidence that the IUS causes additional weight gain
✅ It can be taken by some who cannot use contraception that contains oestrogen
✅ The IUS is not affected by vomiting, diarrhoea or other medicines like some methods of contraception


❌ It does not protect against STIs
❌ It may cause irregular bleeding at first It can cause temporary side effects such as skin problems, headaches or breast tenderness
❌ It can cause small fluid-filled cysts on your ovaries – these usually disappear without treatment and often there are no symptoms
❌ There is a small risk of getting an infection after the IUS is inserted
❌ There is a small risk of the IUS becoming pushed out or the IUS being displaced
❌ There is a very small risk of tearing of the uterus
❌ If you do become pregnant while you are using the IUS there is a small risk of ectopic pregnancy



 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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