Intrauterine Device (IUD) Birth Control: Effectiveness and Types
Written by: Hormone University
Verified by: Kaely McDevitt
If you’re searching for an effective and long-lasting birth control method, an intrauterine device (IUD) birth control may be an option to consider.
Although these T-shaped devices aren’t for everyone, IUDs provide a number of benefits, including reduced risk of pregnancy, longer-lasting protection when compared to the pill or condoms, and convenience.
In this article, we’ll discuss what an IUD is, the different kinds of IUDs, how they work, and how to decide whether or not this birth control method is right for you.
What is an IUD?
An intrauterine device (IUD), sometimes called an intrauterine contraceptive (IUC), is a small, T-shaped device placed inside the uterus to prevent pregnancy.
Once inserted, an IUD can be effective for three to 12 years, depending on the type of IUD you choose.
When were IUDs invented?
According to an article published in the Bulletin of the New York Academy of Medicine, the first recorded IUD insertion was in 1909. Back then, the first IUD invented was designed with a ring made of silkworm gut and two ends that extended from the cervical opening. This allowed him to check the device and remove it — today, IUDs are made with two strings that hang from the cervix and into the vaginal canal.
Who invented the IUD?
A German physician named Dr. Richard Richter invented the first IUD. In 1929, Ernst Gräfenburg, who is also a German physician, created the Gräfenburg Ring, which was a coiled ring of a silver copper-wire mix wrapped in silk thread.
How does an IUD work?
IUDs protect against pregnancy by preventing sperm cells from reaching and fertilizing an egg.
Types of IUDs
There are two types of IUDs: hormonal and nonhormonal (or copper IUDs).
- Copper IUDs: Nonhormonal IUDs are wrapped in copper coil and can protect you from pregnancy for up to 12 years. These IUDs release copper ions into your uterus, forming an inhospitable environment for sperm.
- Hormonal (levonorgestrel) IUDs: Four brands of hormonal IUDs are FDA-approved for use in the United States, including Mirena, Kyleena, Liletta, and Skyla. Hormonal IUDs contain progestin, a form of progesterone, which is released into the body in tiny amounts for a set number of years — the amount and timeline depend on the brand. The progestin then goes to work, thickening the cervical mucus and thinning the uterine lining, making it nearly impossible for an egg to attach or implant to the uterus.
Which IUD type is best?
While both types of IUDs are effective in preventing pregnancy, there are some differences between hormonal and nonhormonal IUDs that could affect your decision about which option is best for you.
Here’s a quick breakdown of what these two types of IUDs have in common (and a few important differences):
- Effectiveness: Both hormonal and nonhormonal IUDs have a high effectiveness rate. According to the Centers for Disease Control (CDC), hormonal IUDs have a failure rate of 0.1-0.4% with typical use, whereas nonhormonal IUDs have a failure rate of 0.8% with typical use. Some IUDs (e.g., Paragard, Mirena, or Liletta) can work as emergency contraception if your doctor inserts the IUD within five days of having unprotected sex. That said, IUDs do not protect against STDs or STIs.
- Longevity: IUDs are long-acting reversible contraceptives (LARC) and can last up to 12 years, depending on the brand.
- Cost: While the upfront cost of an IUD can vary between $0–$1,300, there are no recurring or monthly costs associated with getting an IUD. Plus, most health insurance providers cover birth control.
- Hormones: The most obvious difference between hormonal and nonhormonal IUDs is that one releases progestin, whereas the other releases copper ions. Hormonal IUDs may decrease menstrual pain and make your periods lighter. The nonhormonal IUD, however, may cause cramping and/or heavy menstrual bleeding.
“Some women prefer the copper IUD as it contains no hormones and is a fairly natural form of birth control,” says Dr. Deborah Lee, M.B.Ch.B., a sexual and reproductive health specialist at Dr Fox, an online pharmacy based in London. “However, the addition of progesterone has some amazing benefits.”
How effective are IUDs?
According to the American College of Obstetricians and Gynecologists (ACOG), IUDs are among one the most effective forms of reversible birth control. With typical use, fewer than 1 in 100 women using an IUD will get pregnant.
Because IUDs are inserted into the uterus, there’s no room for human error (e.g., forgetting to take the pill or using it incorrectly, like a condom). Plus, an IUD protects you from pregnancy 24/7 for three to 12 years, depending on the brand you choose.
Once your IUD is in place, you can forget about it until it expires. When it expires, you’ll need to make an appointment to replace it or remove it.
Can anything make an IUD less effective?
There are a few reasons why an IUD might fail, including:
- improper placement
- an abnormally-shaped uterus
- keeping an IUD that’s past its expiration date
The bottom line
IUDs are small, T-shaped devices designed to protect you against pregnancy for three to 12 years. IUDs come in two types: hormonal and nonhormonal. Deciding which IUD option is best for you will depend on several factors, including your medical history, personal lifestyle and preferences (e.g., can you deal with a potentially heavier period? If not, a hormonal IUD may be the better option), and your insurance coverage.
If you’re still on the fence, make an appointment your OB-GYN or an endocrinologist to discuss your IUD options in detail. They should be able to answer any questions and help you determine which IUD birth control method is right for you.