Intrauterine devices, or IUDs, are one of the most popular forms of long-acting reversible birth control. They can prevent pregnancy for years at a time without requiring any extra work on your part.

But what is an IUD exactly? How does it work? How long does it last? Who are IUDs for? How do you get an IUD?

We answer all these questions and more to help you decide if an IUD is the best type of birth control for you.

What are IUDs?

IUDs are small, flexible devices that look like the letter T and are inserted into the uterus to prevent pregnancy. An IUD is called a long-acting reversible birth control because it can remain in place for years, but you can have it removed at any time. (Just keep in mind that it’s possible to get pregnant during your first menstrual cycle after IUD removal.)

There are five brands of IUD in the United States that have been approved by the Food and Drug Administration (FDA): ParaGard, Liletta, Mirena, Skyla and Kyleena. There are some differences between these brands, such as whether they contain hormones and how long they last, which are covered below.

How does an IUD work?

There are two types of IUD: hormonal and nonhormonal. Both are more than 99% effective at preventing pregnancy.

Hormonal IUDs

The majority of IUDs prevent pregnancy by releasing small amounts of the hormone progestin. This prevents eggs from leaving your ovaries and thickens your cervical mucus so that sperm can’t get through.

How long do hormonal IUDs last?

Hormonal IUDs can last for 3-7 years, depending on the brand.

How long does it take for a hormonal IUD to work?

They start preventing pregnancy one week after insertion. During this time, use another form of contraception, such as condoms, to prevent pregnancy.

Nonhormonal copper IUDs

ParaGard is the only nonhormonal IUD – it’s made of copper, which is a natural spermicide.

How long do copper IUDs last?

Nonhormonal IUDs can last for up to 12 years.

How long does it take for a copper IUD to work?

A nonhormonal copper IUD will begin working immediately to prevent pregnancy.

How effective are IUDs at preventing pregnancy?

While the chance of pregnancy with an IUD is less than 1%, there are a few reasons why an IUD could fail at preventing pregnancy, including the IUD moving out of place, or not abstaining from sex for one week after IUD insertion. If your IUD moved, it should be taken out right away. You can check if it moved by feeling for the strings.

What happens if you get pregnant with an IUD?

Again, it’s rare to get pregnant with an IUD, but if you do, you might feel some of the traditional early pregnancy symptoms, such as nausea, fatigue, a missed period or mood changes among others.

An ectopic pregnancy – when the embryo implants outside of the uterus – is more likely to happen if you have an IUD, so if you think you could be pregnant, see your care provider to remove your IUD as soon as possible.

The benefits of IUDs

Because IUDs are inserted at the doctor’s office and can last for several years, there’s no maintenance involved – you don’t need to remember to take a pill every day. They also do not interrupt sex.

Besides pregnancy prevention, hormonal IUDs can also help lighten heavy periods, as well as help relieve painful periods or endometriosis side effects. It also does not cause weight gain.

A nonhormonal copper IUD is a good choice for people who do not want birth control that releases hormones. It can also stay inserted for a longer period of time than a hormonal IUD.

How is an IUD inserted?

An IUD placement begins like a pelvic exam. A speculum, the metal instrument used during a pelvic exam, is inserted into your vagina to allow access to your cervix. A small tube with the IUD in it is inserted through your cervix. The IUD arms are bent back in the tube, and they open once the device is in your uterus. There are strings at the end of the IUD that your doctor may trim. The process usually takes less than five minutes and can be done by an OB-GYN, midwife or nurse practitioner.

Can an IUD be inserted while you’re on your period?

Yes. You can get an IUD inserted at any time during your menstrual cycle, including while you’re on your period. During the last few days of your period, your cervix is naturally open and softer, which makes it an ideal time for an IUD placement. This also ensures that you are not pregnant – an IUD cannot be placed during pregnancy or if you have a pelvic infection.

Does an IUD hurt when it’s inserted?

If you feel pain, it usually only lasts a moment. Most women feel cramping or mild discomfort during the insertion process. After the IUD is inserted, you may feel dizzy or faint. Taking ibuprofen (Advil or Motrin) before and after your insertion appointment can help with discomfort.

What to expect after IUD insertion

Here are common questions about IUDs after insertion:

When can you have sex after IUD insertion?

You can have sex as soon as you’d like to after an IUD is inserted, and it will not move or disrupt the placement of your IUD. You may want to abstain, though, if you’re feeling some cramping or discomfort. (Also keep in mind that if you got a hormonal IUD, it won’t start working to prevent pregnancy until one week after insertion.)

Can your partner feel your IUD?

Your partner usually won’t feel your IUD but it’s possible. If this is happening, you may be able to have the strings trimmed. The strings are about two inches long and can be felt with your finger, up by your cervix. During intercourse, cervical mucus tends to minimize the feel of the strings.

Does an IUD make you bleed?

It’s possible to have light bleeding (spotting) for one or two days after the IUD is placed. For 3-6 months after the insertion of a hormonal IUD, you may experience irregular periods, which includes heavier bleeding and cramping, or spotting in between periods.

For the copper nonhormonal IUD, it’s possible to experience an increase in menstrual bleeding and cramping, but your period may return to normal after about six months.

While you can’t stop IUD bleeding, taking an NSAID like ibuprofen can help reduce bleeding and pain.

Can you use a tampon with an IUD?

Yes, you can use a tampon if you have an IUD. But if you have an IUD placed while you’re on your period, your doctor will likely recommend that you use pads instead of tampons for the first couple days after insertion.

Do IUDs stop periods?

It’s possible for periods to stop while using a hormonal IUD, but not a copper IUD.

If you get a hormonal IUD, it can be common to experience some spotting during the first 3-6 months after insertion. And eventually, it’s possible for your period to stop while the IUD remains inserted, and return after it’s removed.

If you get a copper IUD, you’ll continue to get your period. That’s because there are no additional hormones that will change your cycle or cause you to stop ovulating.

Does an IUD cause weight gain?

No, weight gain is not a side effect of an IUD. If you notice an increase in weight after getting an IUD, it would be from water retention caused by the hormone progestin, which can cause bloating.

What to expect after IUD removal

It only takes a few minutes for a doctor to remove an IUD. This takes place during an office visit. Your doctor will use a speculum, the same metal instrument that was used to insert the IUD, to open your vagina. Then they will use a tool to gently pull the strings of the IUD. The arms of the IUD will fold up as it slides through the cervix and out your vagina.

You might feel some cramping as this is done, so you could take ibuprofen (Advil or Motrin) to help with potential discomfort.

You might experience some light bleeding right after the IUD is taken out, but you can go back to normal activities. You can also become pregnant after the IUD removal, so if you still want to prevent pregnancy, talk with your doctor about other methods of birth control.

How soon after childbirth can I get an IUD?

You can get an IUD immediately after childbirth. However, there’s a greater risk of the IUD falling out or puncturing the uterus if it’s inserted shortly after childbirth. So, your doctor may recommend that you wait until your six-week postpartum appointment. It’s also safe to get an IUD if you’re breastfeeding and it will not impact your milk supply.

I’ve been told IUDs are unsafe. Is this true?

There are some risks to getting an IUD, but they’re very small. Rare complications include malposition and perforation. Malposition is when the IUD has an abnormal position in the uterus. Perforation is when the IUD passes through the wall of the uterus. Your care provider will be careful during placement to avoid these complications, and in some cases, an ultrasound may be used to confirm the IUD’s position.

Many concerns about the safety of IUDs date back to the 1970s. At the time, an IUD called the Dalkon Shield was shown to be ineffective at preventing pregnancy and also caused very serious pelvic infections. But the Dalkon Shield had major design flaws that modern IUDs do not have.

That said, there are some conditions that can make an IUD an inappropriate choice of birth control. You shouldn’t get an IUD if you:

  • Have or might have an STD or other infection
  • Think you might be pregnant
  • Have vaginal bleeding that’s not related to your period
  • Have cervical cancer that hasn't been treated
  • Have cancer of the uterus
  • Have a bleeding disorder or Wilson’s Disease – an allergy to copper (in the case of the copper ParaGard IUD)

Are IUDs covered by insurance?

IUDs are typically covered by insurance because of the Affordable Care Act (ACA), which covers all methods of birth control. But it’s a good idea to check your insurance coverage first.

How much does an IUD cost without insurance?

Without insurance, the cost of an IUD could range from $500 to $1,300. An IUD can last for several years, so it may still be the most cost-effective choice.

Find out if an IUD is right for you

Overall, IUDs are a very convenient form of birth control for many people. You can get the benefits of hormonal birth control without needing to take a pill or change a ring, and you aren’t at risk of using it incorrectly.

Of course, with all the types of birth control that are available, it can still help to talk to a women's health specialist like an OB-GYN, midwife or nurse practitioner about whether an IUD is the method that best fits your needs.

The best first step is to schedule an IUD consultation. If you decide to move forward with an IUD after your conversation, you can leave with an IUD the same day if you choose.