Advantages and disadvantages

Advantages and disadvantages of the IUS


  • It works for 5 years or 3 years, depending on the brand.
  • Your periods can become lighter, shorter and less painful – they may stop completely after the first year of use.
  • It’s safe to use an IUS if you’re breastfeeding.
  • It’s not affected by other medicines.
  • It may be a good option if you cannot take the hormone oestrogen, which is used in the combined contraceptive pill.
  • It’s possible to get pregnant as soon as the IUS is removed.


  • There’s a small risk of getting an infection after it’s been fitted. If you get an infection when you have an IUS fitted, it could lead to a pelvic infection or UTI if not treated.
  • If you have an IUS fitted, you may have a slightly higher chance of getting thrush that keeps coming back. This is because candida spores can anchor to the strings of the IUS and despite treatment, the spores can keep causing reinfections. Speak to a GP if you keep getting thrush. You might want to think about trying a different type of contraception.
  • Your periods may become irregular or stop completely, which may not be suitable for some women.
  • Some women experience headaches, acne and breast tenderness after having the IUS fitted.
  • Some women experience changes in mood and libido, but these changes are very small.
  • An uncommon side effect of the IUS is that some women can develop small fluid-filled cysts on the ovaries – these usually disappear without treatment.
  • An IUS does not protect you against STIs, so you may need to use condoms as well.
  • If you get an infection when you have an IUS fitted, it could lead to a pelvic infection if it’s not treated.
  • Most women who stop using an IUS do so because of vaginal bleeding and pain, although this is less common.

Key points

Key points

It can be used by women who cannot use combined contraception (such as the combined pill) – for example, those who have migraines. Most women can use an IUS, including those who are HIV positive. A GP or nurse will ask about your medical history to check if an IUS is suitable contraception for you. If you’re 45 or older when you have the IUS fitted, it can be left in until you reach the menopause or no longer need contraception. The IUS may not be suitable if you have:
  • breast cancer, or have had it in the past 5 years
  • cervical cancer or womb (uterus) cancer
  • liver disease
  • unexplained bleeding between periods or after sex
  • arterial disease or a history of serious heart disease or stroke
  • an untreated sexually transmitted infection (STI) or pelvic infection
  • problems with your womb or cervix