Overview of the IUD Contraceptive Device

An IUD is a small, flexible contraceptive device that is inserted into the uterus. The letters IUD stand for intrauterine device. An IUD is usually made of plastic and is shaped like the letter T. This contraceptive method is long-lasting, safe and extremely effective.

There are three IUD brands that are available in the United States: Mirena, ParaGard and Skyla. The IUD is the most popular form of reversible birth control in the world. In fact, most women who get an IUD are satisfied with their choice—99 percent of IUD users are pleased with them.

Different Types of IUDs Available in the U.S.
Verywell / Nusha Ashjaee

Mirena IUD

The Mirena intrauterine device (IUD) is made of flexible plastic. It releases a low amount of progestin levonorgestrel continuously over a 5-year period as a way to prevent pregnancy.

According to the manufacturer of Mirena, Bayer HealthCare Pharmaceuticals, this IUD is for women who have had at least 1 child, are in a mutually monogamous relationship, and have no risk or history of ectopic pregnancy or pelvic inflammatory disease. BUT, the American College of Obstetricians and Gynecologists advocates that both women who have never given birth and teens could benefit from using IUDs...this includes using Mirena or the ParaGard IUD.

The Mirena IUD can reduce menstrual cramps, the total amount of monthly period bleeding and has been FDA-approved to treat heavy menstrual bleeding. After removing the IUD, your ability to get pregnant quickly returns.

ParaGard IUD

The ParaGard intrauterine device (also called the Copper T 380A) is about 1-1/4 inches wide by 1-3/8 inches long, made of flexible plastic and wrapped in copper. It is hormone-free. Note that with ParaGard, your periods won't get shorter or lighter; rather, they may get heavier and longer. The ParaGard IUD releases a tiny amount of copper over a 10-year period as a way to prevent pregnancy.

*An Extra Advantage: The ParaGard IUD can be used as a form of emergency contraception. In fact, if inserted within 5 days after unprotected intercourse, ParaGard can lower the risk of pregnancy by 99.9%.

Skyla IUD

Skyla is thought to be "Mirena's little sister." This mini-IUD slowly releases a low amount of the progestin levonorgestrel continuously over a 3-year period. It is smaller than Mirena and contains less progestin. Unlike Mirena, the Skyla IUD has been FDA-approved for use by women of all ages, whether or not they have given birth.

Kyleena IUD

Kyleena is part of the same "family" as Skyla and Mirena. This hormonal IUD also continuously releases a low amount of the progestin levonorgestrel over a period of 5 years. It is smaller than Mirena and about the same size as Skyla. It contains more progestin than Skyla but less than Mirena. Like the Skyla, the Kyleena IUD has FDA-approval to be used by all women, whether or not they have given birth.

How the IUD Works

The Mirena IUD, Skyla IUD, and the ParaGard IUD all prevent sperm from joining with an egg by interfering with the movement of the sperm toward the egg. These IUDs also change the lining of the uterus. In theory, this change to the uterine wall may keep a fertilized egg from attaching to the lining of the uterus, but there is no proof that this actually happens.

For some women, the progestin in the Mirena IUD and Skyla IUD may also prevent ovulation from occurring. The progestin also thickens a woman's cervical mucus, so the thicker mucus can further block sperm from joining with an egg.


Most women can use either IUD safely. But, some increased risk factors may not make the IUD the ideal birth control method for some women.

The IUD must be inserted by a qualified healthcare professional. The IUD insertion usually includes a bimanual examination. The doctor will remove the IUD from its sterile packaging. Then, the arms of the IUD are bent back, and a tube containing the IUD is inserted. The IUD is pushed into place by a plunger in the tube. Once out of the tube and in the proper position, the IUD arms open into the "T" shape.

After Insertion

Some women may still feel some cramping as the uterus adjusts to the placement of the IUD. If this is the case, the cramps should lessen with some time and, perhaps, some rest or pain medication. You may also have some bleeding and spotting during the first few days after insertion.

You can have sex as soon as you feel comfortable after the IUD insertion.

  • ParaGard IUD is effective immediately.
  • Mirena IUD and Skyla IUD are effective immediately only if inserted within 7 days after the start of your period. If inserted at any other time during your menstrual cycle, use another contraceptive like a condom, female condom, Today Sponge or spermicide during the first week after the IUD insertion. Protection will begin after seven days.

STD Protection

An IUD won’t protect you against sexually transmitted diseases.


If an IUD is going to slip out of place, it will most likely happen in the first few months of use or during your period. Check your pads or tampons to see if your IUD has fallen out. If it has, call your doctor and use another birth control method. It is especially important to check the IUD strings every few days for the first few weeks and to feel for the string ends between periods to make sure that the IUD is still properly in place.


The IUD may have a higher upfront cost. But it is the most inexpensive long-term and reversible form of birth control available. Since an IUD's protection can last 5 to 10 years, the expense ends up being less per month than the monthly filling of pill prescriptions.

The costs of an IUD may include:

  • A medical exam
  • The Mirena IUD, ParaGard IUD or Skyla IUD
  • Follow-up visits to your doctor

IUD costs vary among Medicaid and health insurance plans. However, under the Affordable Care Act, non-grandfathered health insurance plans should fully cover (with no copays) the costs to have an IUD inserted, removed, and the cost of the actual device.


You must eventually have an IUD removed since an IUD doesn’t disintegrate and, for the most part, will not come out on its own. The IUD removal procedure is often easier, less painful, and quicker than the insertion.

You must have your IUD removed by a doctor—never try to remove your IUD by yourself or ask an unqualified person to do so as this could cause serious damage. You can have your IUD removed at any time and can have a new IUD replaced during the same visit.

IUD Effectiveness

An IUD is one of the most effective birth control types available. Less than 1 out of 100 women will get pregnant each year if they use the ParaGard, Skyla or the Mirena IUD.

Caution: Most pregnancies happen when an IUD slips out, and you don't realize this has happened. Even though the chance of pregnancy during IUD use is very low, if it does occur, you should contact your doctor as soon as you find out that you are pregnant.

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