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Copper Intrauterine Device (Copper IUD)

The copper IUD is a small plastic device combined with copper, not hormones. It is inserted into the uterus through the cervix, just like a hormonal IUD, but it can stay there for longer.

This article is part of our Contraception Series!


What we're covering

What is it?

How does it work?

How effective is it?

What side-effects could I get?

When can't I use it?

Does it work immediately?

What happens to my fertility if I stop?

Does it protect against STDs?


Note: the information below was sourced from references (1-5), unless stated otherwise.

What is it?

The copper IUD is a small plastic device combined with copper, not hormones. It is inserted into the uterus through the cervix, just like a hormonal IUD, but it can stay there for longer (ten to twelve years, depending on the brand). Placement of an IUD can be very quick (about five minutes), but sometimes it takes longer, or it takes multiple tries.

Insertion of an IUD requires a pelvic examination, in which your doctor will want to look inside your vagina and inspect your cervix and uterus, sometimes also using ultrasound. They will typically first use their fingers, followed by insertion of a speculum. This can be uncomfortable, both physically and mentally. Let your doctor know if you’re nervous for the examination and procedure or if you’re uncomfortable at any time.

Insertion and removal of an IUD can be very painful. You could try over-the-counter painkillers before you go in for your appointment, but evidence suggests they aren’t very effective for the pain caused by IUD insertion or removal. Most doctors can give you local anesthesia before starting the procedure, which is more likely to help. Check with your doctor what options are available for you.

How does it work?

Copper prevents sperm cells from moving around effectively. It also prevents sperm cells from being able to complete fertilization of an egg cell, by inactivating the substance they need to destroy the protective layer around the egg cell.

An IUD has two strings attached to the bottom, which are used by your doctor to take out the IUD and they’re helpful to see if your IUD is still in place. Your doctor might instruct you to regularly feel for the strings hanging from your cervix. This is because people sometimes spontaneously expel their IUD, meaning it’s coming out of your uterus and into your cervix (or out of your body all the way). This happens most often in the first month after placement of the IUD. Recent evidence also suggests that expulsion of an IUD is more common if you use a menstrual cup (6). You may or may not feel this happening, but if you think you lost your IUD, contact your doctor and use other contraception until the presence of your IUD is confirmed.

The strings can also sometimes be uncomfortable for a sex partner, because they might feel them with their penis. This usually doesn’t hurt, but if it does, you can ask your doctor to trim the strings. This can help.

Don’t worry about displacing or moving around an IUD during sex or exercise – this is highly unlikely to happen. A penis, sex toy, or fingers can’t go into the cervix, so they can’t reach the IUD in the womb. Even during penetration with fingers it’s incredibly unlikely to accidentally pull out an IUD. That said, it is possible that your IUD was already being expelled and you only noticed during sex. If you’re having bad cramping or bleeding, or you can feel something hard sticking out of your cervix, contact your doctor.

How effective is it?

The copper IUD is very effective, with nearly 100% protection against pregnancy. With perfect use, only 6 pregnancies per 1000 people* per year occur (a 0.6% chance of pregnancy). With typical use, this is 8 pregnancies per 1000 people* per year (a 0.8% chance of pregnancy).

What are possible side-effects?

The copper IUD, in contrast to the hormonal IUD, often increases your blood flow during menstruation. It also often causes some cramping, especially in the first three to six months after placement. Very rarely, your IUD pokes a hole in the wall of your uterus (perforation).

Some people develop an infection after placement, but this will typically only happen if you had an unrecognized infection of your cervix (for example, due to an STD) at the time of placement. This is why, if you have a higher risk of STD (for example, if you have sexual contact with lots of different people or if you’re a sex worker), your doctor may want to do an STD test before they place your IUD. Your doctor might ask you a few questions about your sexual habits to assess the need for testing.

Lastly, an IUD can increase your risk of an ectopic pregnancy if you do end up becoming pregnant. To learn more about ectopic pregnancy, read this article.

The copper IUD can protect against endometrial cancer.

Note that only a portion of people experience (some of) these side-effects, and some people will experience side-effects not listed here. Whether you will, depends on many different factors.

When can't I use it?

When you’re experiencing pregnancy, pelvic infection (including pelvic inflammatory disease or PID), cancer of the uterus or cervix, certain rheumatic diseases, severe anemia, bleeding from your genitals due to unknown cause, or when your uterus is structured in such a way that an IUD won’t fit (or that it won’t be safe). You also can’t use the copper IUD if you have a copper allergy or if you have Wilson’s disease.

Sometimes, you can get an IUD even if you have one of these things. Talk to your doctor to find out if your health issue would definitely mean you can’t get a copper IUD. Sometimes, you’re still able to get a hormonal IUD instead.

Does it work immediately?

Yes. You’re protected against pregnancy immediately after insertion of the copper IUD. For this reason, the copper IUD can also be inserted as emergency contraception (read more about this here).

What happens to my fertility if I stop using it?

Fertility typically returns in about a month following removal of your IUD (7).

Does it protect against sexually transmitted diseases (STDs)?

No, the copper IUD does not protect against STDs. If you’re having sex with someone new or untested, use a barrier method as well.

*People, here, means anyone who is able to become pregnant, including girls, women, and non-binary people and transgender men who still have their uterus, vagina, and ovaries.

Are you curious about other methods to protect yourself from an unwanted pregnancy? Read about other birth control options here!

This article is pending medical review.


Written by Juliëtte Gossens

Reviewed by Sophie Oppelt and Selina Voßen

Edited by Juliëtte Gossens



  1. McFarlane I (ed.). Seeing the unseen: The case for action in the neglected crisis of unintended pregnancy. United Nations Population Fund. 2022. Available from:

  2. Hacker NF, Gambone JC, Hobel CJ (eds.). Hacker & Moore’s Essentials of Obstetrics & Gynecology. 6th ed. Philadelphia: Elsevier; 2016.

  3. Hoffman BL, Schorge JO, Halvorson LM, Hamid CA, Corton MM, Schaffer JI (eds.). William’s Gynecology. 4th ed. New York: McGraw-Hill Education; 2020.

  4. Centers for Disease Control and Prevention. The United States Medical Eligibility Criteria for Contraceptive Use, 2016 (US MEC). Available from:

  5. Centers for Disease Control and Prevention. 2016 U.S. Selected Practice Recommendations for Contraceptive Use (U.S. SPR). Available from:

  6. Long J, Schreiber C, Creinin M, Kaneshiro B, Nanda K, Blithe D. Menstrual Cup Use and Intrauterine Device Expulsion in a Copper Intrauterine Device Contraceptive Efficacy Trial [OP01-1B]. Obstetrics & Gynecology. 2020;135(5 [Supplement]):15. DOI: 10.1097/01.AOG.0000662872.89062.83

  7. Girum T, Wasie A. Return of fertility after discontinuation of contraception: a systematic review and meta-analysis. Contraception and Reproductive Medicine. 2018;3:9. DOI: 10.1186/s40834-018-0064-y

Please note: the information we provide to you here is for educational purposes only. If you’re experiencing any discomfort or have any complaints or questions about your health, please contact your doctor or other relevant health professional. We don’t provide medical advice.

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