Original article Increased Use of Intrauterine Contraception in California, 1997 to 2007 Kirsten M.J. Thompson, MPH * , Diana Greene Foster, PhD, Cynthia C. Harper, PhD Bixby Center for Global Reproductive Health, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco Article history: Received 12 August 2010; Received in revised form 15 April 2011; Accepted 18 April 2011 abstract Background: Modern intrauterine contraception (IUC) is safe and highly effective, but is used by fewer than 4% of women in the United States. Once recommended only for women with at least one child, it is now recommended for most women regardless of parity or age. Methods: This study used data representative of California women from 10 years of the California Women’s Health Survey (1997–2007) to describe how IUC users differ from women using other contraceptives, and assess changes in IUC users’ characteristics over time. Findings: Overall 4.9% of women in California used IUC. Multivariable logistic regression modeling showed IUC users were more likely to be born outside the United States (odds ratio [OR], 1.7), have a college degree (OR, 1.5) or post- graduate degree (OR, 2.2), and be married (OR, 2.6) or in an unmarried partnership (OR, 2.4). IUC users were 71% less likely to be nulliparous (OR, 0.29). Use of IUC almost doubled over the study period from 4.0% to 7.2%, and this growth was accompanied by significant changes in user characteristics: Young women, women born in the United States, women without a college degree, and Asian women experienced the greatest increases. IUC use among nulliparous women did not increase. Conclusion: IUC use in California is higher than the national average and growing. We found higher IUC use among ever- married women and foreign-born women, and disproportionately low use among nulliparous women. Efforts to inform women of IUC’s high effectiveness and safety, as well as efforts to ensure that health care providers have the necessary clinical skills, are timely and important. Copyright Ó 2011 by the Jacobs Institute of Women’s Health. Published by Elsevier Inc. Introduction Thirty-five years ago, nearly 1 in 10 married women of reproductive age in the United States used intrauterine contra- ception (IUC; Ford, 1978). Its use fell dramatically after 1974, when the Dalkon Shield was shown to cause infertility (Hubacher, 2002). Between 1986 and 1988, there was no IUC sold on the U.S. market. After the introduction of the Copper T 380a intrauterine device in 1988 and approval of the levonorgestrel- releasing intrauterine system in 2000, IUC use remained low. In 2002, IUC accounted for only 2% of contraceptive use in the United States (Mosher, Martinez, Chandra, Abma, & Willson, 2004), and 5.5% from 2006 to 2008 (Mosher & Jones, 2010). By contrast, IUC was the contraceptive method of choice for 7% to 24% of women in a dozen European countries (Sonfield, 2007; United Nations, 2010). The two IUC devices available in the United States today are in the top tier of effectiveness (>99%), have lower discontinuation rates than any other reversible methods, and are highly cost- effective (Trussell, 2008; Chiou et al., 2003; Foster et al., 2009; World Health Organization, 2004). There is a broad consensus within the medical community that IUC is safe for a wide variety of women to use, regardless of age, relationship status, or parity (American College of Obstetricians and Gynecologists, 2007). The U.S. Centers for Disease Control and Prevention (CDC, 2010) evidence-based medical eligibility criteria for contraception indicate most women are good candidates for IUC, including women with histories of pelvic inflammatory disease or ectopic pregnancy. Increasing the access to IUC in the United States may help to reduce the high rates of unintended pregnancy and repeat abortion (Cohen, 2007; Henshaw & Finer, 2003; Speidel, Harper, & Shields, 2008). There are barriers to expanded IUC provision and use. Among medical providers, concerns about IUC provision and Funded by a grant from the William and Flora Hewlett Foundation. * Correspondence to: Ms. Kirsten M.J. Thompson, MPH, University of Cal- ifornia, San Francisco, Department of Obstetrics, Gynecology, & Reproductive Sciences, 3333 California Street, Suite 335, UCSF Box 0744, San Francisco, CA 94143. Phone: (415) 502-4076; fax: (415) 502-8479. E-mail address: thompsonkm@obgyn.ucsf.edu (K.M.J. Thompson). www.whijournal.com 1049-3867/$ - see front matter Copyright Ó 2011 by the Jacobs Institute of Women’s Health. Published by Elsevier Inc. doi:10.1016/j.whi.2011.04.010 Women's Health Issues 21-6 (2011) 425–430