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Other Birth Control Options

How Do IUDs Work?

There are two types of IUDs available in the United States. One type releases the hormone progestin, which causes the cervical mucus to become thicker so the sperm cannot reach the egg. There are two hormone IUDs available: Mirena can be used for up to 5 years and the Skyla can be implanted for up to 3 years.

The other type doesn't use hormones. It contains copper, which is slowly released into the uterine cavity. The copper stops the sperm from making it through the vagina and uterus to reach the egg, thus preventing fertilization. There is one copper IUD available, the ParaGard T380A, which can be kept in place for up to 10 years.

How Effective Is the IUD?

The IUD is 99% effective.

How Is an IUD Used?

Once the IUD has been inserted by your doctor, you do not need to take any further steps to prevent pregnancy until it is time to replace it. How long it lasts depends on the type of IUD you receive.

Do IUDs Protect Against Sexually Transmitted Diseases?

No. IUDs do not protect against STDs, including HIV (the virus that causes AIDS). The male latex condom provides the best protection from most STDs.

Are There Side Effects Associated With IUDs?

IUDs rarely cause serious side effects when used in a monogamous relationship (having only one sex partner). Side effects include, painful and heavy periods or frequent spotting, backaches, and headaches. Discuss these side effects with your doctor.

Mirena is associated with lighter menstrual periods.

Are There Risks Associated With IUDs?

IUDs carry some health risks. They include:

  • Menstrual problems. The copper IUD may increase menstrual bleeding or cramps. Women may also experience spotting between periods. The hormonal IUD may reduce menstrual cramps and bleeding.
  • Perforation. In 1 out of 1,000 women, the IUD will get stuck in or puncture (perforate) the uterus. Although perforation is rare, it almost always occurs during insertion. The IUD should be removed if the uterus has been perforated.
  • Expulsion. About 2 to 10 out of 100 IUDs are pushed out (expelled) from the uterus into the vagina during the first year. This usually happens in the first few months of use. Expulsion is more likely when the IUD is inserted right after childbirth or in a woman who has not carried a pregnancy. When an IUD has been expelled, you are no longer protected against pregnancy.

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