IUDs, Implants Most Effective Reversible Contraceptives

Laurie Barclay, MD

June 22, 2011

June 22, 2011 — Long-acting reversible contraceptives (LARCs), namely intrauterine devices (IUDs) and contraceptive implants, are the most effective reversible contraceptives, according to a Practice Bulletin—Gynecology released June 20 by the American College of Obstetricians and Gynecologists (ACOG).

The Bulletin, entitled "Long-Acting Reversible Contraception: Implants and Intrauterine Devices" is published in the July 2011 issue of Obstetrics & Gynecology and offers information regarding appropriate patient selection and management of clinical issues and complications associated with LARC use.

"LARC methods are the best tool we have to fight against unintended pregnancies, which currently account for 49% of US pregnancies each year," said Eve Espey, MD, MPH, coauthor of the Practice Bulletin, in a news release. "The major advantage is that after insertion, LARCs work without having to do anything else. There's no maintenance required."

The 3 LARC methods available in the United States are the copper T380A IUD, the levonorgestrel intrauterine system, and the etonogestrel single-rod contraceptive implant. All must be inserted in the physician's office. Return of fertility is rapid once the device is removed.

The copper IUD effectively prevents pregnancy for 10 years by releasing a small amount of copper into the uterus, which prevents fertilization or implantation of a fertilized egg to the uterine wall and interferes with sperm motility. When inserted within 5 days of unprotected sex, it can also be used for emergency contraception.

Ovulation continues in women using the copper IUD, which may increase menstrual bleeding and cramping. These symptoms may decrease with time, but heavy menstrual bleeding and dysmenorrhea are the leading causes of IUD discontinuation.

The hormonal IUD releases progestin into the uterus, which thickens cervical mucus, thins the uterine lining, and may reduce sperm motility. Duration of contraception with the hormonal IUD is 5 years. Because the hormonal IUD may make menstrual cycles lighter, it is also approved by the US Food and Drug Administration (FDA) for treatment of menorrhagia.

The contraceptive implant has a pregnancy rate of 0.05%, making it the most effective method of reversible contraception available. A matchstick-sized rod is inserted under the skin of the upper arm, allowing controlled release of an ovulation-suppressing hormone for up to 3 years.

"Women need to know that today's IUDs are much improved from earlier versions, and complications are extremely rare," Dr. Espey said. "IUDs are not abortifacients—they work before pregnancy is established—and are safe for the majority of women, including adolescents and women who have never had children. And while upfront costs may be higher, LARCs are much more cost-effective than other contraceptive methods in the long run."

Recommendations — Level A Evidence

Specific ACOG recommendations and conclusions based on good and consistent scientific evidence (Level A) are as follows:

  • Before IUD insertion, routine antibiotic prophylaxis is not recommended to prevent pelvic infection.

  • When inserted up to 5 days after unprotected intercourse, a copper IUD is the most effective method of postcoital contraception.

Recommendations — Level B Evidence

Specific ACOG recommendations and conclusions based on limited or inconsistent scientific evidence (Level B) are as follows:

  • Women with a history of ectopic pregnancy may be offered IUDs.

  • Insertion of the implant is safe at any time after childbirth in women who are not breast-feeding.

  • Women who are breast-feeding may be offered implants at 4 weeks after childbirth or later.

  • Immediately after either an abortion or miscarriage, insertion of an IUD or implant is safe and effective.

  • Immediate postpartum IUD insertion (within 10 minutes of placental separation) appears to be safe and effective.

Recommendations — Level C Evidence

Specific ACOG recommendations and conclusions based primarily on consensus and expert opinion (Level C) are as follows:

  • Because of theoretic concerns about milk production and infant growth and development, the US Medical Eligibility Criteria for Contraceptive Use classifies placement of an implant in breast-feeding women less than 4 weeks after childbirth as Category 2.

  • Nulliparous women and adolescents can be offered IUDs and other LARC methods.

  • When possible, IUDs should be removed from pregnant women without an invasive procedure, according to the FDA and the World Health Organization.

  • There are few contraindications to LARCs, and almost all women are eligible for implants and IUDs.

  • As long as pregnancy may be reasonably ruled out, an IUD or an implant may be inserted at any time during the menstrual cycle.

  • For women at high risk for sexually transmitted infections (STIs), such as those 25 years or younger or women having multiple sex partners, it is reasonable to screen for STIs and place the IUD on the same day (and give treatment if the screen result is positive) or when the test results are available.

  • Patients should be counseled about the effects of LARCs on menstrual bleeding.

  • Endometrial biopsy or sampling, cervical colposcopy, and cervical ablation or excision may be performed with an IUD left in place.

A performance measure proposed in the Practice Bulletin is the percentage of eligible women seeking contraception who are offered LARC.

"Encouraging the use of LARC methods for appropriate candidates may help lower U.S. unintended pregnancy rates because gaps in use and discontinuation of shorter acting methods are associated with unintended pregnancy rates in high-risk women," the Bulletin authors write. "Typical-use pregnancy rates for LARCs are lower, and continuation rates are higher, when compared with oral contraceptives. In an economic analysis, both types of IUDs were among the three least expensive contraceptive methods over a 5-year period."

Obstet Gynecol. 2011;118:184-196. Abstract


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