What is an Intrauterine Device (IUD)?

From the Guidelines

Intrauterine devices (IUDs) are a highly effective and safe form of long-acting reversible contraception, with a failure rate of less than 1%, and are suitable for adolescents and nulliparous women, as supported by recent studies 1.

Key Characteristics of IUDs

• There are two main types: hormonal IUDs (like Mirena, Kyleena, Liletta, and Skyla) and copper IUDs (like Paragard)
• IUDs can last from 3 to 12 years depending on the type
• They are over 99% effective at preventing pregnancy
• Insertion is a simple office procedure that takes a few minutes
• Common side effects include irregular bleeding or spotting, which usually improves over time

Benefits and Considerations

• Hormonal IUDs can lead to lighter periods or no periods at all, while copper IUDs may cause heavier periods initially
• IUDs do not protect against sexually transmitted infections, so condoms are recommended if STI protection is needed
• Fertility returns quickly after removal of the IUD
• IUDs are suitable for adolescents and nulliparous women, with no increased risk of pelvic inflammatory disease or infertility

Recommendations for Use

• IUDs can be inserted at any time, with no need for backup contraception for copper IUDs, but 7 days of backup contraception may be needed for levonorgestrel IUDs if inserted more than 7 days after menses started 1
• A bimanual examination and cervical inspection are recommended before insertion
• Screening for gonorrhea and chlamydia may be performed at the time of IUD placement, but placement should not be delayed unless there is a current infection 1

From the Research

Intrauterine Device Overview

• Intrauterine devices (IUDs) are placed in the uterine cavity to provide long-term contraception, mainly by preventing fertilization 2.
• The best-known IUDs contain copper, but there is also an IUD delivering levonorgestrel, a progestin 2.

Effectiveness of IUDs

• T-shaped copper IUDs and the levonorgestrel-releasing device have similar contraceptive efficacy as combined oral contraceptives that are used correctly 2.
• IUDs are more effective than oral contraception used incorrectly 2.
• Among IUD users, there are on average about 6 pregnancies per 1000 woman-years 2.
• The levonorgestrel IUD seems to be at least as effective as copper IUDs 2.

Adverse Effects of IUDs

• The rare intrauterine pregnancies that occur in women using an IUD generally end in miscarriage 2.
• About 25% of these pregnancies end in a live birth if the device is left in place, compared to about 90% if the device is removed 2.
• Ectopic pregnancies are rarer in IUD users than in women who do not use contraception 2.
• The IUD is expelled in about 5% to 10% of cases within 5 years, and expulsion recurs in about 30% of these women 2.
• Problems such as difficult insertion, pain, bleeding, and syncope are reported in less than 1.5% of cases overall 2.

Comparison of IUDs

• Copper-containing IUDs are more effective than depot progestogens at preventing pregnancy 3.
• The copper IUD was associated with a reduction in HIV disease progression compared to depot progestogen or oral contraceptive 3.
• Progestin IUDs may be effective for emergency contraception, but more research is needed to confirm this 4.

Clinical Practice and Recommendations

• IUDs can be safely used by most women and should be considered the first-line method of contraception for all women 5.
• Extended use of IUDs beyond the manufacturer-approved time period may be possible, but more research is needed to determine the risks and benefits 6.
• Clinicians should consider patient characteristics and preferences, as well as country- and community-specific factors, when counseling about IUD use 6.