One of the most important medical interventions to improve maternal-child health is providing effective contraception to men and women of reproductive age. The 52-mg levonorgestrel-intrauterine device (LNG-IUD; Mirena) is one of the most effective forms of reversible contraception available to women, with a failure rate of 1.1% over 5 years of use.1 The TCu380A copper-IUD (ParaGard), another highly effective reversible contraceptive, is reported to have failure rates of approximately 1.4% and 2.2%, over 5 and 10 years of use.2
An interesting question is whether—in certain clinical situations—a single IUD can be used for longer than the currently recommended 5 and 10 years for a Mirena IUD and a ParaGard IUD, respectively.
The LNG-IUD containing 52 mg LNG may be effective up to 7 years
The US Food and Drug Administration (FDA) package insert for the Mirena 52-mg LNG-IUD states that the device is “indicated for contraception for up to 5 years. Thereafter if continued contraception is desired, the system should be replaced.”1 The FDA package insert for the levonorgestrel-releasing intrauterine system, Liletta 52-mg LNG-IUD, states that it is “indicated for prevention of pregnancy up to 3 years.”3 The FDA guidance is based on data submitted to the agency by the manufacturers to support the approval process. Completing large-scale clinical trials that extend past 5 years or more is challenging, because of the cost and the loss of study participants to follow-up. Hence, few clinical trials of contraceptive IUDs continue for more than 5 to 10 years.
Although the FDA-approved indication for Mirena and Liletta is 5 and 3 years, respectively, evidence suggests that the 52-mg LNG-IUD is an effective contraceptive beyond 5 years. In fact, multiple studies report that this IUD is an effective contraceptive for at least 6 or 7 years (TABLE 1).4–9 Among 895 women using the 52-mg LNG-IUD for 6 to 7 years, only 1 pregnancy was reported in the last year of use. In that case, the IUD was in the cervix and partially expelled from the uterus.8 These data indicate that the 52-mg LNG-IUD is likely an effective contraceptive for up to 7 years, with pregnancy rates below 1% in the last year of use.
The TCu380A copper-IUD is effective up to 12 years
The currently available TCu380A copper-IUD (ParaGard) is FDA approved for 10 years.2 Studies evaluating the efficacy of this copper-IUD are limited, but those that have been published reported that it is effective for at least 12 years and possibly up to 20 years (TABLE 2).10−13
Recently I saw a patient who had a copper-IUD (ParaGard, TCu380A) inserted as a teen after a birth, and had successfully used the same device for 17 years. She presented for removal of the IUD so that she could attempt conception. After removal of the IUD, copper wire was visible on the device. Long-term studies of the TCu220 copper-IUD, which contains less copper than the ParaGard, report pregnancies with the use of the device beyond 10 years.12 These devices, which are not available in the United States, should not be used past their recommended interval.