What Are IUDs?

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An intrauterine device (IUD) is a small, flexible, plastic device that is shaped like the letter T. It gets inserted into the uterus where it can stay for several years to prevent pregnancy. It may be removed earlier for any reason, including if a woman wants to try to conceive.

IUDs are the most popular form of long-acting, reversible birth control in the world. Once an IUD is inserted, a woman does not have to worry about contraception until it needs replacing. Some IUDs may also make menstrual periods lighter or stop a woman from having them altogether.

While safe and more than 99% effective in preventing pregnancy, IUDs do not prevent the transmission of sexually transmitted diseases.

This article discusses how IUDs work, what brands are available, and how each of them are different.

How IUDs Work

IUDs work by interfering with how sperm move, which in turn prevents fertilization.

There are two types:

  • Hormone-releasing IUDs thicken cervical mucus, which makes it harder for sperm to enter the uterus.
  • The copper IUD creates a toxic environment for sperm.

Each brand of IUD is different. Most women can use either type safely, though there are some exceptions.

Because IUDs are meant to offer protection from pregnancy for several years and can be removed at any time, they are considered a form of long-acting reversible contraception (LARC).

Different Types of IUDs Available in the U.S.

Verywell / Nusha Ashjaee

Brands of IUDs

Five IUD brands are available in the United States.

One of these, Paragard, is a non-hormonal IUD made of copper. The other four—Kyleena, Liletta, Mirena, and Skyla—work by releasing small amounts of levonorgestrel (a type of progestin hormone) over time.

These IUDs differ in how big they are and how much hormone (if any) they release.


Effective for: Up to 10 years

The Paragard IUD (also called the Copper T 380A) is the only hormone-free IUD on the U.S. market. It's made of flexible plastic and wrapped in copper.

For some patients, the Paragard IUD can cause longer, heavier periods. For this reason, it is not recommended for women with endometriosis or other conditions that cause heavy periods.

Because copper is toxic to sperm, Paragard can also be used as a form of emergency contraception. In fact, if inserted within five days after unprotected sex, it can lower the risk of pregnancy by 99.9%.


Effective for: Up to six years

The Liletta IUD is made of soft, flexible plastic and contains 52 milligrams (mg) of the hormone levonorgestrel.

Liletta should not be used in women with endometriosis or a risk/history of pelvic inflammatory disease (PID).

If you were recently pregnant, talk with your healthcare provider about how long you need to wait before a Liletta IUD can be safely inserted.


Effective for: Up to seven years

The Mirena IUD is made of flexible plastic and contains 52 mg of levonorgestrel. It is the largest and strongest of three IUDs manufactured by Bayer Healthcare Pharmaceuticals.

In 2021, the U.S. Food and Drug Administration (FDA) approved Mirena for up to seven years of use, making it the longest-acting hormonal IUD on the market.

Mirena is recommended for women who have had at least one child and have no risk or history of ectopic pregnancy or pelvic inflammatory disease.

The Mirena IUD can reduce menstrual cramps. It has been FDA-approved to treat heavy periods.


Effective for: Up to five years

Kyleena is also made by Bayer. It is smaller than the Mirena IUD and contains 19.5 mg of levonorgestrel.

The Kyleena IUD is approved for use in all women, regardless of whether they've given birth. However, it is not recommended in women with a risk or history of pelvic inflammatory disease.


Effective for: Up to three years

Skyla contains 13.5 mg of levonorgestrel and is the lowest dose IUD made by Bayer.

Like the Kyleena IUD, Skyla is approved for use in women of all ages, regardless of whether they've given birth. It is not recommended for women with a risk or history of pelvic inflammatory disease.


If you're thinking about an IUD for birth control, there are hormonal and non-hormonal options. Talk to your healthcare provider about which of the five approved IUDs might work best for you based on your risk factors, individual preferences, and uterus size.

IUD Insertion

IUD insertion must be done by a qualified healthcare professional. They may recommend that you take an over-the-counter pain medicine before your appointment to help ease any discomfort the procedure may cause.

In addition to reviewing the insertion process before beginning, your provider will take time to go over benefits, risks, alternative options, and expectations of an IUD.

You will be asked to sign an informed consent form acknowledging that this information has been reviewed. Be sure to ask any questions you have at this time.

The provider will verify the size and position of your uterus by performing a bimanual exam. This is when they place two fingers of one hand into the vagina and press on your belly with the other hand.

The insertion takes about five minutes. The procedure follows the same general steps no matter what type of IUD is being used.

Here's a topline view of what happens during Kyleena insertion as an example:

  • The provider removes the insertion tool with the IUD attached from its sterile packaging. They then slide a button on the tool so that the IUD's arms fold up into a long, thin tube.
  • The tube containing the IUD is inserted into the vagina and moved into the uterus.
  • The provider slide the button on the tool again, this time in the other direction, to push the IUD into place. Once out of the tube and in the proper position, the IUD arms open into the "T" shape.
  • Strings attached to the bottom of the IUD are trimmed.

After Insertion

Some women experience cramping as the uterus adjusts to the placement of the IUD. This usually lasts for a few days, though it can persist for three to six months. Cramps should lessen with time, rest, and/or pain medication.

You may also have some bleeding and spotting during the first few days after insertion.

Pelvic inflammatory disease (PID) is a rare complication after IUD placement. Contact your healthcare provider right away if you experience any of the following symptoms of PID:

  • Fever
  • Pain in your lower abdomen
  • Unusual vaginal discharge or bad odor
  • Burning sensation when you pee

When Can I Have Sex After Getting an IUD?

Talk to your healthcare provider about how soon you can safely resume sexual activity after your IUD is inserted.

Paragard is effective immediately. However, hormonal IUDs must be placed at certain points in your cycle to take effect right away.

If they are not placed within a week of your period, you'll likely need to use another form of birth control for about a week after insertion to avoid getting pregnant.


Like other medical devices, an IUD can shift position or come out. Most pregnancies happen when an IUD slips out of place and you don't realize it.

It's important to pay attention to your IUD, especially in the first few months of use and during your period (when your cervix is more open).

You can do this by watching your pads or tampons to see if your IUD has fallen out.

You can also feel for the strings between periods. However, never grab hold of/tug on the strings themselves, as this can cause the device to move out of position. Always use clean hands.

If your IUD comes out, contact your healthcare provider and use another form of birth control until you can have a new one inserted.

Even though the chance of pregnancy during IUD use is very low, if you get pregnant with an IUD in place, you should contact your practitioner immediately.


Inserting an IUD is a short procedure performed in your healthcare provider's office. Once your IUD is in place, it's important to make sure it stays there. To do that, feel for the removal strings and watch your pads and tampons during your period to make sure it hasn't fallen out. If it does, contact your healthcare provider.


An IUD may seem more expensive than other forms of monthly birth control because you pay the cost upfront.

However, since an IUD's protection can last three to 10 years, it is one of the most inexpensive long-term and reversible forms of birth control available.

The costs of an IUD may include:

  • A medical exam
  • The cost of the device
  • Follow-up visits to your healthcare provider

The cost of an IUD can vary depending on your medical coverage. For some, an IUD may be completely covered by insurance.


Just like IUDs must be inserted by a healthcare professional, they must also be removed by one (they do not disintegrate over time).

Some women opt to have their IUD removed before it is time if they want to start trying to have a baby or simply prefer to switch to another form of contraception. Others choose to keep it in place until it's about to expire.

The IUD removal procedure is often easier, less painful, and quicker than insertion. If you are replacing your IUD, a new one can be inserted during the same visit.

Never try to remove your IUD by yourself or ask an unqualified person to do so, as this could cause serious damage.


An IUD is one of the most effective birth control types available, and nearly all women with them in place are pleased with them.

If you're considering an IUD, talk to your practitioner about which one is best for you. Of the five on the market, four contain hormones and one does not.

If you've had an IUD inserted, it's important to take steps to make sure it remains in place. Remember to talk with your healthcare provider about any concerns you have and make sure you have the device removed on time.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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