Data reaffirm the effectiveness of LNG, copper intrauterine devices

Findings from a recent analysis of data from a large, multi-country study of women using levonorgestrel or copper intrauterine devices (IUDs) indicate that while both forms of contraception have high levels of efficacy, the levonorgestrel device daily releasing 20 mcg (Mirena LNG IUD, Bayer Healthcare Pharmaceuticals, Wayne, NJ) was associated with a significantly lower risk of pregnancy, including ectopic pregnancy, than copper IUDs.¹

The study, called the European Active Surveillance Study for Intrauterine Devices, included more than 61,000 women from Austria, Finland, Germany, Poland, Sweden, and the United Kingdom. A prospective, controlled, long-term cohort study, the study is believed to be the largest to date to document contraceptive efficacy, adverse events, and potential risk factors for uterine perforation in intrauterine contraceptive users.

Recruitment of study participants between ages 18-50 was conducted through a network of healthcare professionals, such as gynecologists and midwives who regularly insert IUDs, who practice in private offices or specialized clinics. All women with a newly inserted IUD were eligible for enrollment. Because the study was conducted in Europe, where more types of copper IUDs are available, the copper IUD cohort included more than 30 types of copper devices. Thirty-seven percent of the women in the copper IUD cohort used Nova-T (200 or 380) devices (Bayer, Wuppertal, Germany). Other devices included the T Safe Cu 380 (Williams Supply, Rhymney, South Wales) with 18% using it, and Multiload CU (250 or 375) (Multilan AG, Dublin, Ireland) with 14% using it.1 Following a baseline survey, study participants and their physicians completed one follow-up questionnaire after 12 months. A multi-faceted follow-up procedure minimized loss to follow-up.

The analysis includes validated follow-up information on 58,324 women: 41,001 women used the levonorgestrel IUD, and 17,323 women selected copper IUDs, resulting in 44,633 and 17,703 woman years of observation, respectively.

A total of 118 contraceptive failures occurred in the trial; 26 in the levonorgestrel device group and 92 in the copper device group. Data indicate that both types of IUDs were highly effective with overall Pearl indices of 0.06 (95% confidence interval [CI]: 0.04-0.09) and 0.52 (95% CI: 0.42-0.64) for levonorgestrel device and copper device groups, respectively. The adjusted hazard ratio for levonorgestrel device versus copper device group was 0.16 (95% CI: 0.10-0.25). Twenty-one pregnancies were ectopic (seven in the levonorgestrel device group and 14 in the copper device group), yielding an adjusted hazard ratio for ectopic pregnancy of 0.26 (95% CI: 0.10-0.66).¹

This study contains new information, says Anita Nelson, MD, professor in the Obstetrics and Gynecology Department at the David Geffen School of Medicine at the University of California in Los Angeles. Previous studies from Europe had not isolated the efficacy of the T380A copper IUD from the lower dose T200 IUDs, which used to be more frequently used in those countries, says Nelson. However, because both of the IUDs are very effective, the choice for levonorgestrel or copper intrauterine contraception probably still depends upon the woman’s preference in bleeding patterns, she notes.

Several aspects of this study are of interest to Robert Hatcher, MD, MPH, professor emeritus of gynecology and obstetrics at Emory University School of Medicine in Atlanta. First, it is a very large study: 58,324 women between ages 18-50 were included in the final analysis. There was very small loss to follow-up during the one-year follow-up period: 1.7% for LNG users and 2.8% for copper IUD users.¹

Second, most of the women receiving copper IUDs received a device with a copper surface area of 300 mm2, but Hatcher says it is curious that the failure rate for women with a larger surface area (300 mm2 or more) actually was slightly higher than the failure rate in the women receiving a copper IUD with a copper surface area of less than 300 mm2. The Pearl indices for copper IUD with less than 300 mm2 was 0.56 (95% CI: 0.24-1.09), and 0.62 (95% CI: 0.50-0.78) for 300 mm2 or greater.¹

Third, there is quite a debate these days as to whether women should be taught to check for the strings of their IUDs, says Hatcher. This study very strongly suggests that women should be taught, he notes. Among users of LNG IUDs who became pregnant, exactly 50% (13 of 26) occurred after an unrecognized IUD expulsion, and 16 of 92 of pregnancies in users of copper IUDs occurred after unrecognized IUD expulsion, Hatcher points out. “Both A Clinical Guide for Contraception and Contraceptive Technology recommend quite clearly that women check for their IUD strings after each menstrual flow,”^2,3 says Hatcher.

The LARC (Long-Acting Reversible Contraception) Program of the American College of Obstetricians and Gynecologists (ACOG) has just published a resource highlighting “hands-on” clinical training opportunities for LARC methods, including information about training for the copper IUD, LNG IUD, and contraceptive implant. (Visit http://bit.ly/1vH4NK2 for the resource.)

Structured, hands-on LARC insertion training outside of academic environments is sometimes difficult to find, particularly for IUD insertion, noted Eve Espey, MD, MPH, chairman of the ACOG LARC Work Group in a LARC program update. Suggestions about other training opportunities, including sessions at professional conferences and other meetings, can be sent to Shirley Kailas at [email protected].

Free, accredited on-demand webinars covering a wide range of topics related to LARC provision are available at http://bit.ly/1J3LVKQ. All webinars are free, and ACOG membership is not required. A variety of LARC-related sessions, as well as the ACOG LARC Program’s annual family planning session in partnership with the Association of Reproductive Health Professionals, will be offered at the ACOG Annual Clinical and Scientific Meeting in San Francisco May 2-6. (Visit http://bit.ly/1AgcCrP for meeting information.)

For information on postpartum insertion of IUDs, check out free online training developed by Cardea, a training, organizational development research group with offices in Texas, California, and Washington, for the Washington State Department of Health in Olympia. Presented by Sarah Prager, MD, MAS, vice chair of the ACOG Committee on Health Care for Underserved Women, the online training addresses intrauterine and subdermal contraception immediately following childbirth. The course addresses indications for immediate postpartum LARC insertion, features videos to demonstrate best practices for postpartum IUD insertion, including how to construct a postpartum uterus model for simulation training, and describes complications and appropriate management strategies. It is designed for providers, counselors, and administrative staff who work in prenatal care or labor and delivery settings. (Visit http://bit.ly/16ZoO2i for more information.)

REFERENCES

1. Heinemann K, Reed S, Moehner S, et al. Comparative contraceptive effectiveness of levonorgestrel-releasing and copper intrauterine devices: The European Active Surveillance Study for Intrauterine Devices. Contraception 2015; doi:10.1016/j.contraception.2015.01.011.
2. Speroff L, Darney PD. A Clinical Guide for Contraception. Philadelphia: Lippincott Williams & Wilkins; 2011.
3. Dean G, Schwarz EB. Intrauterine contraceptives (IUCs). In: Hatcher RA, Trussell J, Nelson AL, et al. Contraceptive Technology: 20th revised edition. New York: Ardent Media; 2011.