Intrauterine Device (IUD)

What is an IUD?

The letters "IUD" stand for "intrauterine device." The IUD is a safe and highly effective form of long-acting reversible contraception (LARC). IUDs are small, "T-shaped" contraceptive devices made of flexible plastic. IUDs are inserted into the uterus by a medical provider with special training.

There are currently 3 types of IUDs available on the United States; The Paragard (a plastic T wrapped with copper wire which can be left in place for up to 12 years), the Mirena (a plastic T which releases the hormone progesterone and can be left in place for up to 5 years), and the Skyla (like the Mirena but a little smaller and can only be left in place for up to 3 years). The Skyla was designed for insertion in younger women who have never given birth, but can be used in any woman.

The IUD is the reversible contraceptive method used by more women across the globe.

How does it work to prevent pregnancy?

It isn't precisily known how IUDs prevent pregnancy but the general assumption is that they prevent the sperm from fertilizing ova (eggs). The IUD is a foreign body which creates an environment not hospitable to sperm. The Paragard releases copper ions which impair sperm function. In addition, the Mirena and Skyla release progestin which causes thickening of cervical mucus which blocks movement of the sperm, thins the lining of the uterus, and ovulation may be suppressed due to the systemic effect of the hormone.

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How effective is the IUD in preventing pregnancy and STIs?

The IUD is one of the most effective methods of contraception available. Less than 1 in 100 women will get pregnant each year using the Paragard, Mirena or Skyla IUD.  However, IUDs do not offer any protection against sexually transmitted infections (STIs).

What are the benefits of using an IUD?

  • IUDs have a good safety record.
  • IUDs offer an alternative to birth control pills for women who can't use a method containing estrogen.
  • IUDs are cost effective over time.
  • Convenient and private.
  • Long term protection which can be revered easily and quickly.
  • Decreased bleeding and cramps with Mirena and Skyla.
  • An IUD can be put in place immediately after a pregnancy has ended (whether by termination, miscarriage or delivery).
  • Paragard can be placed in the first 3 days after unprotected intercourse as a form of emergency contraception.
  • Decreased risk of endometrial cancer.
  • Decreased risk of ectopic (tubal) pregnancy.

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What are the disadvantages of using an IUD?

  • The procedure for insertion can be uncomfortable, with cramping and pain immediately following insertion.
  • Increased menstrual cramps and bleeding for some women with the Paragard.
  • Irregular bleeding with the Mirena and Skula, particularly in the first few months after insertion. Some women will stop having peridos with theses IUDs, which is safe but which may or may not be desirable for some women. Mirena has a higher rate of amenorrhea (the absence of menstrual bleeding) than Skyla.
  • Very small risk of perforation of the uerus.
  • There is a 2-10% risk of explusion of the IUD in the first year. This risk is increased in women who haven't had children, who are under age 20, who are immediately post-partum, or who have severe cramps or heavy bleeding. There is a 30% risk of expulsion if someone has had a previous IUD expulsion.
  • Small risk of infection.
  • Some women using the Mirena or Skyla will experience progestin side effects. Most of these side effects are local rather than systemic and are reduced over time, but some women experience breast change, moodiness and acne.
  • Paragard has no hormonal benefits. Somen women who have had decreased cramps, bleeding or acne on oral contraceptives may find that these symptoms worsen if they switch to the Paragard.

Who should not use an IUD?

The choice to use an IUD is one you will make after a discussion with your provider. The following are some conditions which may be contraindications to the insertion of an IUD:

  • Pregnancy
  • Active pelvic infection
  • Allergy to copper or Wilson's disease (Paragard)
  • Allergy to levonorgesterel (Mirena or Skyla)
  • Unexplained vaginal bleeding
  • Anemia due to heavy periods (Paragard)

Past concerns about IUDs

There are many lingering misconceptions about this form of birth control. One is that IUDs are dangerous, causing infection and infertility. A type of IUD called the Dalkon Shield was removed from the market in the 1980s. It caused serious infections due to a design flaw. Reviews of the medical literature point to a very low risk of infection or infertility among current IUD users. Another misconception is that the IUD is only for women who have given birth. We now know that the IUD can be inserted and used safely by women of all ages who have never given birth.

Where can I go to get an IUD and how much does it cost?

Health Services does not insert IUDs. However, medical providers can advise students who are interested in an IUD and can offer referrals. Brown students can make an appointment by calling 401.863-3953.The IUD is covered by most insurance companies. You can call your health insurance company to find out what your out of pocket cost would be, if any.

Links you can use:

For more information about IUDs you can visit:

Planned Parenthood

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