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revised Wednesday April 22 2009
healthy sexuality
Birth Control Methods

IUD (Intrauterine Device)

An IUD is a small plastic or copper device that fits inside the uterus.

An IUD prevents pregnancy by slowing the sperm as they move toward the egg and by altering the lining of the uterus so that a fertilized egg is not able to attach to the uterine wall.

IUD Types

IUDs available in Canada are made of copper or plastic and are shaped like a T. One type of IUD also contains a hormone which increases its effectiveness in preventing pregnancy.

Each IUD has thin plastic strings attached to it that hang through the cervix into the vagina. The strings are approximately 1-2 inches long. These strings can’t be felt by your partner during vaginal sex.  At least once a month, females that use an IUD will need to check if they can still feel the strings to be sure that the IUD is in place. An IUD should be replaced between 1-5 years.

All IUDs must be inserted and removed by a doctor.



The effectiveness rate for the copper IUD is between 99.2 percent and 99.9 percent, meaning virtually no females out of 100 who use it for one year will get pregnant.

The effectiveness rate for the hormonal IUD is 99.9 percent, meaning virtually no females out of 100 using it for one year will get pregnant.

* source: The Mayo Clinic


Advantages & Disadvantages



  • Doesn't interrupt sex.
  • Doesn't require your partner's involvement.
  • Highly and immediately effective.
  • Requires no daily attention.
  • Isn't messy.
  • Doesn't protect against sexually transmitted infections including HIV/AIDS.
  • Requires visits to a doctor or clinic for insertion and removal.
  • Cramping and discomfort during insertion.
  • Expulsion or partial dislodging of the IUD.
  • Can cause longer and heavier periods unless you are using the hormonal IUD.
  • If you get an STI, it could increase the likelihood of Pelvic Inflammatory Disease (PID), which may lead to infertility.

Cautions & Things to Consider

The IUD Doesn’t Protect Against STIs

An IUD won’t protect you or your partner from STIs including HIV/AIDS. Using an IUD and condoms at the same time can reduce your chances of getting an STI, including HIV/AIDS.

IUDs Aren’t for Everyone

You may not be able to use an IUD if:

  • You have - or have experienced - Pelvic Inflammatory Disease (PID).
  • You’ve had a recent (within last 3 months) or recurrent STI.
  • You’re pregnant or think you might be pregnant.
  • You have undiagnosed or irregular uterine bleeding.
  • You’ve had an abnormal pap test or you might have uterine cancer.
  • You have anemia or bleeding disorders.
  • You have AIDS or are HIV-positive.

The hormonal type of IUD may address some of the difficulties and side effects related to bleeding. Speak to your doctor or health care professional to see if the IUD with hormones is right for you.

Side Effects

Possible side effects and complications from using an IUD include:

  • Longer and heavier periods with more cramps (this may decrease with time)
  • Expulsion or partial dislodging of the IUD.
  • Increased risk of infection, Pelvic Inflammatory Disease (PID) and possible transmission of HIV (more likely with multiple partners) and do not use condoms.
  • Spotting or bleeding between periods.
  • A slightly increased risk of PID during the first 3 weeks after the IUD is inserted (The chance of PID increases if you or your partner has other partners) and do not use condoms.
  • Perforation of the uterus at the time of insertion (rare).

Before having an IUD inserted, get tested for STIs.


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Revised: Wednesday April 22 2009

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