IUS (intrauterine system)

The IUS, or intrauterine system is a small, T-shaped plastic device that is inserted into your womb (uterus) by a specially trained doctor or nurse. It releases a small amount of progestogen into the womb and this thickens the mucus from your cervix, making it difficult for sperm to move through and reach an egg.

It also thins the womb lining so the period is likely to become very light and in many women may stop completely.

The IUS is a long-acting reversible contraceptive (LARC) method. It works for five years or three years, depending on the type, so you don't have to think about contraception every day or each time you have sex.

It's more than 99% effective, depending on which type is used.

If you have no symptoms and want a straightforward test you can:

  • either order a smart kit online for home delivery
  • or attend one of our clinics where you can collect a smart kit without needing to wait and see a clinician.

This is a quick, easy and confidential way to screen for chlamydia, gonorrhoea, HIV and syphilis.

Call our appointments line for more information about sexual health services in Merton, Richmond and Wandsworth.

0333 300 2100 (Mon-Fri 8am-8pm).

Read more about IUS via the NHS Choices website