What is an IUS?

  • An IUS is a small piece of plastic that a health care provider can insert into a female uterus to prevent pregnancy.
  • It is T-shaped. It has a small reservoir that slowly releases a hormone.

How does an IUS work?

  • The IUS reservoir releases a hormone called progestin into the lining of the uterus.
  • The hormone makes the cervical mucous thicker. This makes it harder for sperm to get into the uterus.
  • The hormone also thins the lining of the uterus, making it harder for a fertilized egg to stick to the uterus. Even if an egg is released and fertilized, it will not continue to grow.
  • Some people do not ovulate when they are using an IUS.
  • It prevents pregnancy 99.9% of the time.
  • An IUS can prevent pregnancy for 3 to 5 years, depending on the type. At this time, it can be removed and a new one put in, if desired.
  • An IUS can be removed at any time by a health care practitioner.

Where can I get an IUS?

  • See a health care provider who will give you a prescription. (If you need a regular health care provider, call the Family Doctor Finder at 204-786-7111 or toll-free at 1-866-690-8260, or go to www.gov.mb.ca/health/familydoctorfinder.) If you are under 22 years old you may also go to a teen clinic.
  • Take your prescription to a pharmacy to buy the IUS.
  • Take the IUS back to your health care provider to have it put in.
  • It can be expensive. If cost is a problem, talk to your health care provider or your community health centre.

How do I use an IUS?

  • The health care provider will do a pelvic exam (internal exam). They will insert a speculum (instrument) into your vagina to see your cervix and wash it with an antiseptic solution.
  • Next, they will insert an IUS into your uterus. In most cases this takes only a few minutes. It can feel uncomfortable, so you may want to ask for pain pills ahead of time.
  • The health care provider will leave the two plastic threads or strings that hang down through the cervix into the vagina. These strings are very thin and do not hang outside the body.

Does an IUS protect me from STIs or HIV?

  • No. Using safer sex supplies every time you have sex reduces the risk of getting an STI (sexually transmitted infection) or HIV infection.
  • Get tested regularly for STIs and HIV.

Are there side effects?

Side effects are caused by the hormones from the IUS which affect the hormonal balance of the body. This is part of how they work.

Minor side effects include:

  • Some discomfort when the IUS is put in.
  • Irregular bleeding for the first three to six months.
  • No period after one year of use for some females.

In rare cases, some may experience:

  • Ectopic pregnancy.
  • Uterine perforation, where the IUD punctures the uterus wall.

Your health care provider will assist if any of these happe

If you are concerned about the effects of hormones on your body, consider an Intra-Uterine Device (IUD) instead. See SERC’s Fact Sheet on IUD’s.

What else do I need to know?

  • If you get a sexually transmitted infection (STI) with an IUS in place, you may get PID. PID could damage your reproductive organs and can cause pain and other serious problems.
  • You may have an STI and not have any symptoms. If you have had unprotected sex, it is important to go to a community health centre or walk-in clinic and ask for an STI test.
  • See your health care provider right away if you have any signs of an infection, such as fever, chills, unusual discharge or smelly discharge. You need to receive treatment to stop the infection from developing into PID.

What do I do if my IUS comes out?

  • Call your health care provider.
  • Use another kind of birth control, such as condoms.

What do I do if I want my IUS taken out?

  • You must see a health care provider. Do not try to take an IUS out by yourself.

Where can I get more information?

  • From your health care provider, community health centre, or public health nurse. If you need a regular health care provider, call the Family Doctor Finder at 204-786-7111 or toll-free at 1-866-690-8260, or go to www.gov.mb.ca/health/familydoctorfinder.
  • From a teen clinic, if you are under 22 years old.
  • From the Facts of Life On-Line: e-mail your questions to thefactsoflife@serc.mb.ca.
  • From websites: www.sexualityandu.ca or www.serc.mb.ca.

Developed in collaboration with Klinic Community Health and Literacy Partners of Manitoba 2007


Cervix – The lower part of the uterus that opens into the vagina.

Ectopic pregnancy – A pregnancy which starts to grow in one of the fallopian tubes, instead of inside the uterus.

Emergency Contraception – Medication used as soon as possible after sex, if other forms of birth control failed or were not used. These can be bought from a pharmacist, or acquired at a community  health centre such as Klinic or Women’s Health. EC is only effective if taken within 5 days of the sex act. If you can’t afford the pharmacy cost, talk to a health provider at a community health centre for options.

Fallopian Tube – The egg travels down this tube from the ovary to the uterus.

Hormone – A chemical substance produced in the body that controls and regulates the activity of certain cells or organs.

Ovulate – To produce and release an egg cell from an ovary.

Pelvic inflammatory disease (PID) – An infection of the uterus, the fallopian tubes or ovaries, which is caused by bacteria. Early treatment of PID is the best way to prevent infertility and other health problems.

Sexually transmitted infection – Infections caused by parasites, viruses or bacteria that are passed from one person to another through sex.

Speculum – An instrument used by health practitioners; it is inserted into the vagina to spread the vaginal walls apart so the cervix can be examined.

Sperm – The male reproductive cells; carried out of the penis in the semen during ejaculation.

Uterus – Part of the female reproductive system, the uterus is a pear-shaped, hollow organ. If an egg cell is fertilized with a sperm, it nests within the uterus and a fetus begins to grow inside of it. The uterus is also called the “womb”.

Vagina – The muscular tube that connects the cervix to the outside of the female body; where the menstrual blood comes out from the uterus, where a baby comes out from the uterus during childbirth, and where a penis or sex toy can go in for vaginal intercourse.

SERC believes that all individuals have the right to access unbiased sexual and reproductive health information and services. They must also have the opportunity to explore their values and attitudes in making informed choices that are most appropriate for them, and have those choices respected and supported. SERC supports and defends a pregnant person’s right to choose parenting, adoption, or abortion.

Developed in collaboration with Klinic Community Health and Literacy Partners of Manitoba 2007
Sexuality Education Resource Centre 2016