The Intrauterine Device (IUD): A Long-acting Reversible Contraception

Approximately, eighty-five out of 100 people who do not use any birth control will get pregnant in one year. All birth control methods have different success rates in preventing pregnancy. For example, condoms can fail about 13% of the time, and birth control pills can fail about 7% of the time, even when used perfectly.

These methods do not fail as often because they stay in place and there is a lower chance of using them incorrectly. Because of this, the failure rate is less than 1 in 100, leading to many fewer unintended pregnancies. LARC methods include subcutaneous (under the skin) implants, intrauterine devices (IUDs), and injectable methods (a shot). The shot fails at a higher rate than other LARC methods because it does not last as long. Besides preventing pregnancies, LARC methods can have other benefits and most people are good candidates for LARC methods. This page will tell you more about IUDs.

IUDs

IUDs are small, bendable implants shaped like a T that are put inside the uterus (womb). There are two kinds of IUDs in the United States: the copper IUD and the hormonal IUD. The copper IUD (ParaGuard®) is wrapped with coils that put small amounts of copper into the uterus, which harms sperm, and can be left in place for up to 12 years. There are four kinds of hormonal IUDs: Mirena®, Kyleena®, Liletta®, and Skyla ®. The hormonal IUD has progestin, a lab-made progesterone-like hormone that thickens the mucus in the cervix (at the base of the uterus) to keep sperm from going into the uterus. It also changes the inside of the uterus so that menstrual bleeding is lighter. Hormonal IUDs can be used for 3-8 years, depending on type.

Most people with a hormonal IUD do not bleed as much with their periods and have fewer cramps after the first few months. IUDs must be put in and taken out by a healthcare provider (i.e. doctor, nurse practitioner, or physician assistant). IUDs work very well at preventing pregnancy while they are in place inside the uterus but can be removed by a healthcare provider when you are ready for pregnancy without any delay in your fertility. IUDs, however, do not stop you from getting sexually transmitted infections (STI). IUDs can be used as emergency contraception if placed within 5 days of unprotected sex. As of 2017, about 14% of women in the United States chose an IUD as their birth control method.

What are some of the concerns about IUDs?

In the past, some people in the US have worried about using IUDs because they thought IUDs might cause an infection in their lower belly (pelvis) or prevent them from being able to have a child. Research studies have shown this is not true. In fact, there is a very low risk of infection with IUD insertion itself. Furthermore, having an IUD does not increase your risk of getting a sexually transmitted infection (STI) or having issues with tubal scarring (which could lead to infertility). There is also a small risk of the IUD falling out of the uterus (happens <1-8% of the time). However, getting the IUD placed by a trained healthcare provider and checking the strings frequently can reduce this risk.

Who can use an IUD?

Before 2005, IUDs were mainly recommended to people who had at least one child, had no history of pelvic infections, and who had a sexual relationship with just one partner. In 2005, the US Food and Drug Administration said using the copper IUD was okay for people who had never had a child and who had more than one sexual partner.

In 2012, the American Congress of Obstetricians and Gynecologists (ACOG) said that both non-hormonal and hormonal IUDs could be used by teens, unless the teen had a pelvic infection in the past. This makes IUDs a good form of birth control for most people. Both kinds of IUDs are safe to use during breastfeeding and can be put into the uterus right after birth.

Who should not use an IUD?

The US Centers for Disease Control has rules for birth control called Medical Eligibility Criteria (CDC MEC). These rules look at different diseases and health conditions and the kinds of birth control that can be used with them. If an IUD can be used by someone with a certain disease without problems, then it is Category 1. For example, obesity (being overweight) is a Category 1 condition, so IUDs can be used by obese people.

A Category 2 condition is when the IUD can be used, but a healthcare provider should follow them more closely. Examples of Category 2 problems are diabetes and emphysema.

Category 3 is a condition in which an IUD is generally not recommended, and a health care provider should carefully consider other options.

Category 4 is a disease or problem that an IUD cannot be used with, such as someone with an active pelvic infection or cervical cancer. Both the copper and hormone IUDs are listed in Category 1 or 2 for most health conditions.

Summary

Hormone and copper IUDs are safe, long-acting methods of birth control that work well. They can be used even with health conditions. Past concerns about IUDs are mostly not true, as studies have not shown that IUDs cause infections or scarring of the tubes that could keep someone from being able to get pregnant. Furthermore, fertility should resume without delay after removal of an IUD. Talk with your healthcare provider about whether the IUD is right for you.