The IUD rumor mill: Common misconceptions
Many women and providers share concerns about IUDs as a method of contraception.
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Long-acting reversible contraception (LARC), which includes both subcutaneous implants and intrauterine devices (IUDs), is the most effective form of contraception. Nurse practitioners and physician assistants who are knowledgeable about IUDs and can anticipate the concerns of patients and other providers are well-positioned to increase IUD use. This may help decrease the number of unplanned pregnancies in the United States.
Around the world, rates of IUD usage are high; for instance, rates in Uzbekistan are 50%, in Vietnam 31%, in China 41%, in Egypt 36%, and in Finland 23%.1 However, in the United States, only 5.2% of women of reproductive age use IUDs.1 This is despite the fact that methods of LARC are the most effective form of birth control aside from abstinence and have an efficacy rate of more than 99%.2 Like vasectomy and female sterilization, methods of LARC are rated Tier 1, the most effective form of contraception, by the World Health Organization and the U.S. Centers for Disease Control and Prevention.3
This article explores potential reasons for the low rates of IUD usage in the United States, despite high rates of usage elsewhere in the world and the high rates of efficacy associated with this method of contraception. Because 98% of women on LARC are using IUDs (as opposed to subcutaneous contraceptive implants),4 this article focuses mainly on IUD usage and perceptions. It will address common patient and provider misconceptions regarding the use of IUDs. Different types of IUDs will be described, including what is currently available in the United States and patient satisfaction, contraindications, side effects, and complications with each type, with the intent of clarifying how many of these common concerns are misplaced.
Types of IUDs
Of the 3 IUDs currently available in the United States, two are hormonal. These two contain differing amounts of the hormone levonorgestrel (LNG). LNG decreases sperm motility by thickening cervical mucus and also makes changes to the endometrium to prevent implantation.
The first hormonal IUD, the LNG-releasing intrauterine system (Mirena; Bayer HealthCare Pharmaceuticals, Wayne, NJ), contains 52 mg of LNG and releases 15 mcg/d to 20 mcg/d. It can stay in place for up to 5 years. The second hormonal IUD, the LNG intrauterine system 13.5 (Skyla; Bayer HealthCare Pharmaceuticals), contains 13.5 mg of LNG, is slightly smaller, and releases approximately 6 mcg/d.5 It can be left in for no more than 3 years.
Nonhormonal and made of copper, the third IUD (Paragard; Teva Women's Health, North Wales, PA) can stay in place for up to 10 years. The copper ions in this IUD prevent sperm motility and the activation of enzymes needed for sperm survival. These spermicidal mechanisms prevent fertilization (Table 1).6