Not Your Mother’s IUD: Benefits and Risks of Modern IUDs

National Women’s Health Network

Women’s Health Activist Newsletter
January/February 2011

By Ginny Cassidy-Brinn

I had an Intrauterine Devices (IUD) in the 70s, when a feminist outcry exposed serious problems caused by the Dalkon Shield IUD, including infertility, uterine perforation, and death. The Dalkon Shield was removed from the market and its manufacturer declared bankruptcy after paying millions of dollars in malpractice settlements. So, I was skeptical when a young feminist told me she loved her IUD and said: “For my generation, IUDs represent freedom and empowerment.” What had happened in the 40 years between my experience and hers, I wondered? Had the IUD really been transformed?

What I found when I looked into these questions was not simple. Thanks to persistent advocacy by the Network and other women’s health activists, today’s IUDs are safer and more popular, and seem to have fewer negative effects than those I knew in the 70s. But the IUD’s place in the array of modern contraception is not without problems. Challenges connected to both cost and coercion can undermine the benefits of this important contraceptive option.

Hormonal & Non-hormonal IUDs

Two types of IUDs are available in the U.S: ParaGard and Mirena. Both are tiny, T-shaped polyethylene devices that, when inserted into the uterus, are over 99% effective at preventing pregnancy. (IUDs do not protect against HIV or other sexually transmitted infections [STIs].) It’s not known precisely how IUDs work, because it is hard to study conception without disrupting it, but they probably prevent conception by preventing sperm from travelling to, and penetrating, the egg; the fertilized egg from travelling to the uterus; and the embryo from implanting in the uterine wall.

ParaGard is effective for up to 10 years, and has been available in the U.S. since 1988. Its design includes a small amount of copper, which improves efficacy and comfort while reducing the IUD’s size. Heavier menstrual periods are a common side effect of ParaGard. Mirena, which has been available in the U.S. since 2001, was developed to address the severe menstrual bleeding and cramping that many ParaGard users experience. (Constant light bleeding or spotting is common with either IUD, but total blood loss is much lower with Mirena.) Effective for up to five years, Mirena includes the hormone progestogen to minimize cramping and bleeding; 20% of Mirena users stop having menstrual periods within a year (periods return when Mirena is removed). For those who don’t stop bleeding, regular and unpredictable periods and light spotting are common. Additional side effects of Mirena’s hormone content include: moodiness, headaches, acne, increased appetite, weight gain, and decreased sex drive and ability to orgasm. Many Mirena users do not experience any of these problems, however.

Since Paragard tends to increase menstrual cramping and bleeding, women with extremely painful or heavy periods may prefer Mirena. Women who want to avoid artificial hormones, or who don’t want to interfere with their natural menstrual cycle, may prefer Paragard. Choosing between the IUDs would be easier if a woman could predict how her body would react to the copper or hormonal content, but IUDs seem to affect each woman differently. Fortunately, if the negative effects are unacceptable, an IUD can be painlessly removed in seconds; 10-25 percent of women have their IUD removed in the first year, most often due to irregular bleeding. Among women who keep their IUD for at least a year, many feel much the same as they did before it was inserted and are happy with it.

Who Can Use the IUD & Who Decides?

Studies done in the 70s, 80s, and early 90s showed an increase in serious pelvic infections and infertility among IUD users. As a result, for many years, practitioners strongly cautioned women against getting an IUD if they wanted to have children later, and often refused to provide IUDs to childless women due to fears about infertility. IUDs were also routinely denied to women who were not in long-term, stable relationships because of concerns they might get an STI that could be exacerbated by an IUD.

The Dalkon Shield (which was included in these studies) had a design flaw such that its string acted as a wick, pulling bacteria into the uterus, causing significant health risks. More recent studies of better-designed IUDs indicate the risk of pelvic infection is increased only in the first 20 days after an IUD is inserted. This is most likely because the woman had a pre-existing STI. In the last 25 years, STI testing has become much more available and more accurate, making it possible to identify and treat STIs before IUD insertion. In a recent study, clinicians tested and treated women for STIs before IUD insertion and found that IUD users had no higher chance of experiencing pelvic inflammatory disease or infertility than women without an IUD.

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Author: Leslie Carol Botha

Author, publisher, radio talk show host and internationally recognized expert on women's hormone cycles. Social/political activist on Gardasil the HPV vaccine for adolescent girls. Co-author of "Understanding Your Mood, Mind and Hormone Cycle." Honorary advisory board member for the Foundation for the Study of Cycles and member of the Society for Menstrual Cycle Research.