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Intrauterine device (IUD)

What is it?

The IUD (also known as the Coil) is a long-acting reversible contraception (LARC). An IUD is a small device (about the size of a matchstick) made from plastic and copper that is inserted into the womb by a specially trained doctor or nurse. It is a long-acting method which protects against pregnancy for up to five to 10 years, depending on the type.

The IUD can also be used as a method of emergency contraception which you can read more about here.

This method does not protect you against sexually transmitted infections (STIs), so you may need to use a condom as well to help protect you against most STIs.

The intrauterine device How does it work?

The IUD works by:

  • Stopping sperm from reaching a released egg
  • Making it more difficult for the egg to settle in the womb

The intrauterine device How effective is it?

There are different types of IUD. Newer IUDs contain more copper and are the most effective – more than 99%.

What are the benefits?

  • You do not have to remember to take a pill every day
  • You are protected against pregnancy for up to five to 10 years
  • Does not interrupt sex
  • Can be used as emergency contraception up to five days after unprotected sex at any time in the menstrual cycle provided this is the only unprotected sex that has occurred since the last period or, within 5 days from the earliest estimated date of egg release (ovulation)
  • Can be used while breastfeeding
  • Can be removed at any time by a trained healthcare professional, if you decide you want to become pregnant
  • Does not contain any hormones
  • It is not affected by other medicines or by diarrhoea and vomiting

The intrauterine deviceWomen may not be able to/may not want to use it if they:

  • Don't want any changes to their periods
  • Don't want to have a small procedure to fit and remove the device

Women should not use it if they:

  • Think that they might already be pregnant
  • Are at risk of getting a sexually transmitted infection, or their partner is
  • Have an untreated sexually transmitted infection or pelvic infection
  • Have problems with their uterus or cervix
  • Have unexplained vaginal bleeding (for example, between periods or after sex)

The intrauterine device Possible side-effects?

As with all medicines side effects can occur but not all women will experience side-effects. Side effects may include:

  • Women may have changes in menstrual patterns
  • Risk of infection after fitting in the first 20 days
  • Risk of ectopic pregnancy (baby develops outside the womb)
  • There is a risk that the IUD might go through (perforate) your womb or cervix when it is put in, but this is rare when inserted by an experienced healthcare professional. This may cause pain, but there may be no symptoms
  • The IUD can be pushed out by your uterus (expulsion) or it can move (displacement)

The intrauterine device What if......?

I use the IUD as emergency contraception?

The emergency IUD is highly effective. However, if it does fail resulting in pregnancy, there is a risk that the IUD can cause a miscarriage or an ectopic pregnancy may occur. If you know that you are pregnant or think you might be, seek medical advice as soon as possible.

An appointment should be made with a health professional approximately three to four weeks after the IUD has been fitted. This is to:

  • Check that you are not pregnant
  • Discuss any problems experienced with the IUD
  • Remove the IUD if this is what you want (this must be done by a trained healthcare professional)

I want to remove it?

A trained doctor or nurse can take the IUD out at any time

I want to become pregnant?

A trained doctor or nurse can remove the IUD at any time. Ideally you should wait for one period before trying to get pregnant. Waiting means the pregnancy can be dated more accurately, and you can seek some pre-pregnancy advice from your healthcare professional.

Remember: Contact your doctor or nurse if you have any concerns or are worried / unsure about anything to do with your contraception.

Have you decided which might be the right contraception for you? If not check out the other choices, if you have, jump to Step3: How do I change?

© 2015 Merck Sharp & Dohme Ltd. All rights reserved.

Job code: WOMN-1160817-0000

Date of preparation: September 2015

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