Contraception Iuds

An intrauterine device (IUD) is a type of birth control inserted into the uterus that may or may not contain hormones. Copper birth control IUDs (marketed in the United States as ParaGard®) don’t contain hormones. Hormonal types of IUDs are also available (called Mirena® IUDs in the United States).

Both types of IUDs are effective in their own way, though some people may prefer to use a certain type of IUD over any others for various reasons.

How Do Birth Control IUDs Work?

Hormonal types of IUDs, such as the Mirena® brand, release the hormone levonorgestrel, a synthetic progesterone, which thins the lining of the uterus. Thus, Mirena® IUDs prevent eggs from being implanted into the uterus. In addition, the mucus that surrounds the uterus becomes thick, physically preventing sperm from entering. In some cases, the levonorgestrel in Mirena® IUDs prevents ovulation entirely. A Mirena® IUD can be effective for five years in certain women.

Copper IUDs work differently. The reasons why ParaGard® and other copper birth control IUDs work isn’t entirely clear. Medical experts, however, speculate that the copper surrounding these IUDs prevents fertilization by increasing spermacidal effects. Also, since copper IUDs don’t prevent ovulation, some sperm may actually fertilize eggs, but the embryo is prevented from reaching the uterus due to the IUD.

IUD - Intrauterine Devices - Birth Control

How is an IUD Implanted?

Before inserting different types of IUDs, your doctor will need to perform a:

  • PAP test
  • Pelvic exam
  • STD culture.

The small T-shaped plastic device is then inserted into the cervix by way of the vagina, and then pushed into the uterus. Typically, a doctor will perform a check-up examination three months after a birth control IUD has been inserted.

Birth Control IUD’s Side Effects and Benefits

As with any other form of birth control, both copper and hormonal IUDs have benefits and risks.

The benefits of using an IUD include:

  • Copper IUDs can be used by women who are presently breastfeeding
  • They can be removed at any point
  • They eliminate the need to take a pill every day
  • They often lessen menstrual pain
  • They work as soon as they are inserted.

However, there are some risks associated with using both types of of IUDs, including:

  • 1 out of every 1,000 women will experience uterine puncture following the placement of an IUD. When this occurs, surgery may be necessary in order to remove the IUD and repair the uterus.
  • Nearly 7 percent of IUDs will be rejected by the body. When this occurs, the IUD simply slips out of the body, sometimes leading to pregnancy.
  • Risk of ectopic pregnancies is increased if a woman becomes pregnant while wearing an IUD.
  • Some women may experience a vaginal infection once an IUD has been implemented.
  • Women who have had a copper IUD inserted may experience an increase in menstrual flow.

Are IUDs Safe for Everyone?

Women who have the following conditions should not use any types of IUDs:

  • Genital Lesions
  • History of ectopic pregnancy
  • Pelvic Infection
  • Salpingitis (inflammation of the fallopian tubes).

Furthermore, women who are allergic to copper or suffer from Wilson’s disease should not use copper IUDs.

You shouldn’t use hormonal IUDs, such as Mirena® IUDs, if you:

  • Are breastfeeding
  • Have breast cancer
  • Have diabetes.

Pregnancy is another factor: if you think you might be pregnant, you shouldn’t have an IUD implanted.


American Pregnancy Staff. (n.d.). IUDs. Retrieved February 10, 2010, from the American Pregnancy Web site:

Birth Control Comparison Staff. (n.d.). IUD info. Retrieved February 10, 2010, from the Birth Control Comparison Web site: Staff. (2010). IUDs: Paragard. Retrieved February 10, 2020, from the Contracept Web site:

Shanahan, K. (2009). Types of IUDs. Retrieved February 10, 2010, from the iVillage Web site: