There are several different types of intrauterine devices (IUDs). Each one has differences that may suit people based on individual needs.
About 10 percent of people on birth control use IUDs. These devices significantly reduce the risk of unintended pregnancy and remove the possibility of human error that comes with taking a pill every day or using condoms.
The best IUD for an individual depends on their medical history, lifestyle, and personal preferences, as well as any side effects that they may experience.
IUDs are sometimes called long-acting reversible contraception (LARC). This name refers to their ability to prevent pregnancy for many years, although people can get pregnant quickly following their removal.
People can choose between two main types of IUD:
Hormonal IUDs release progestin, which is a synthetic version of the hormone progesterone. Progestin thickens the mucus in the cervix, which makes it nearly impossible for sperm to reach the egg.
Progestin also thins the lining of the uterus. In the unlikely event that sperm can travel to the egg, this thin lining makes it difficult for an egg to implant in the uterus and cause a pregnancy.
There are four different brands of hormonal IUDs:
- Mirena can prevent pregnancy for up to 6 years
- Kyleena can work for up to 5 years
- Liletta works for as long as 4 years
- Skyla prevents pregnancy for up to 3 years
Nonhormonal or copper IUDs
Copper IUDs do not use hormones. Instead, the copper damages sperm to prevent it from getting to the egg. It also creates an immune response that stops the development of healthy eggs and destroys any eggs that do develop.
In the United States, the brand name of the copper IUD is ParaGard.
ParaGard IUDs begin working immediately, so doctors may choose them when emergency contraception is necessary. The copper IUD can prevent pregnancy for up to 10 years and possibly longer.
As with any birth control, the IUD offers benefits but also carries risks. People may wish to talk to a doctor about their medical history and any plans regarding future pregnancy before deciding which IUD is right for them.
The pros and cons of different types of IUD include:
The benefits of hormonal IUDs include:
- Highly effective: Both hormonal and nonhormonal IUDs are over 99 percent effective. However, a 2015 study found that hormonal IUDs are more effective than copper IUDs.
- More regular periods: Some people find that the hormones in an IUD regulate their periods or even make their periods disappear.
- Lower the risk of certain cancers: The hormones in the IUD may reduce the risk of some cancers, including cancer of the endometrium, which is the lining of the uterus.
However, hormonal IUDs may not be suitable for people with pelvic infections, uterine distortions, unexplained vaginal bleeding, and cervical or endometrial cancer.
The benefits of the copper IUD include:
- No hormones: Copper IUDs are safe even for people who cannot use hormonal birth control.
- Emergency contraception: A copper IUD begins working immediately, so it can function as an emergency form of birth control.
- Longer lasting: While both copper and hormonal IUDs can work for many years, copper IUDs should prevent pregnancy for at least 10 years.
The drawbacks of copper IUDs include:
- Heavier periods: Some people experience heavier periods with a copper IUD. Therefore, these IUDs may not be a good choice for people who have painful periods or endometriosis.
- Copper allergies: People who have an allergy to copper or Wilson’s disease cannot safely use copper IUDs.
Intrauterine devices can be an excellent contraception choice for many people.
The benefits of both hormonal and copper IUDs include:
- Reduced chance of human error: A healthcare professional will insert the IUD into the uterus. Once the IUD is in place, the individual does not have to worry about forgetting to take a pill or use a condom.
- High effectiveness: IUDs are highly effective. The pregnancy rate with these devices ranges from 0.9 to 1.5 percent, which is much lower than the rates of other nonpermanent forms of birth control.
- Providing long-term contraception: IUDs are safe to use for many years. They may even remain somewhat effective past their recommended end date.
- Protection against pregnancy-related health issues: For people with severe health conditions that make pregnancy dangerous, an IUD can be life-saving.
- Affordability: An IUD does not require frequent visits to the doctor or repeat prescriptions. As a result, it is a more affordable option for many people, especially when health insurance covers it.
- Flexibility: As long as there is no possibility of a woman being pregnant, the IUD insertion can take place at any point during her monthly cycle. It is not necessary to wait for a period to start or end.
IUDs are not suitable for everyone. In a small percentage of people, IUDs can cause serious complications.
The risks and drawbacks of IUDs include:
- Insertion pain: People may experience pain when the healthcare professional inserts the IUD. Some describe intense pain, while others report minimal pain or no pain at all. A skilled doctor can often perform a less painful insertion. Taking ibuprofen or another nonsteroidal anti-inflammatory drug (NSAID) before the procedure can help.
- Pelvic inflammatory disease (PID): In a small number of people, an IUD can irritate the uterus and cervix, causing a painful condition called PID. This risk is only present for the first month after insertion.
- Coming out of the uterus: In about 1 in 1,000 people, the IUD falls out of the uterus. This movement does not usually cause any complications, although it can reduce the effectiveness of the device. A healthcare professional will need to take out an IUD that has moved.
- Pregnancy complications: In the unlikely event that someone gets pregnant while using an IUD, the rate of pregnancy complications is much higher. These complications may include miscarriage, preterm labor, infection following a miscarriage, and ectopic pregnancy. A 2012 study found that removing an IUD as soon as someone detects a pregnancy can lower the risk of complications.
Many people find that IUDs offer the right combination of effectiveness, safety, and minimal side effects.
People who are considering using an IUD should discuss their options with a doctor to select the best type for them. There are many other hormonal or nonhormonal birth control options available for people who are unable to use an IUD.