Intrauterine devices reported effective for emergency contraception
In recent months the morning after pill Plan B One-Step, manufactured by Teva Health, has sparked considerable attention. However, alternative methods of emergency contraception are available. Specifically, the intrauterine device (IUD) has been employed for that use. A new study set out to evaluate the effectiveness of the IUD for that purpose. The study was published online on May 8 in the journal Human Reproduction.
Researchers affiliated with Princeton University as well as investigators in Shanghai and South Africa conducted a review study regarding the use of an IUD for emergency contraception. They found that the insertion of an IUD within five days of unprotected intercourse was more effective in preventing pregnancy than the morning after pill. The authors noted that IUDs have been studied for use for emergency contraception for at least 35 years. They add that IUDs are safe and highly effective for emergency contraception and regular contraception, and are extremely cost-effective as an ongoing method.
The researchers reviewed 274 studies and found that 42 met their inclusion criteria. To locate appropriate studies, they reviewed the medical literature, including the following databases: Medline, Global Health, Clinicaltrials.gov, Popline, Wanfang Data (Chinese) and Weipu Data (Chinese). They included studies published in English or Chinese, with a defined population of women who presented for emergency contraception and had an IUD inserted; they included studies in which the number of pregnancies was determined and those that describe the number of women who were lost to follow-up. Data from each study was independently evaluated by two reviewers.
The studies were conducted in six nations between 1979 and 2011 and comprised a total of 7,034 women. Eight different types of IUDs were inserted; the time from intercourse to IUD insertion ranged from two days to 10 or more days. The majority of insertions (74%) were performed within five days of intercourse. The pregnancy rate (excluding one outlier study) was 0.09%. In comparison, the morning after pill has a significantly higher pregnancy rate: 1-3%. The study authors also cited a recent California study that reported that 85% of contraceptive providers in the state never recommend an IUD for emergency contraception. They also noted that IUD usage in the US for contraception—not emergency contraception—has increased in recent years; the 1995 rate of 1% rose to almost 5% in 2010.
The authors concluded that IUDs are a highly effective method of contraception after unprotected intercourse. The noted that because they are safe for the majority of women, highly effective and cost-effective when left in place as ongoing contraception, whenever clinically feasible IUDs should be included in the range of emergency contraception options offered to patients presenting after unprotected intercourse.
The authors noted that a limitation of their study was that the original studies did not provide sufficient data on the delay between intercourse and insertion of the IUD, parity (number of previous pregnancies), cycle day of intercourse, or IUD type to allow analysis by any of these variables.
An IUD is a small plastic device that is inserted into the uterus. Two types are available in the US: the hormonal IUD and the copper IUD. The hormonal IUD lasts for five years, while the copper IUD lasts up to 10 years. IUDs are among the most effective methods of contraception. During the first year of use, the risk of pregnancy is less than 1%.
Take home message:
Despite their effectiveness, a number of reasons impact the popularity of IUDs. Cost is a significant deterrent. The morning after pill costs from $10 to $70; however, an IUD insertion costs $500 or more. An IUD can cause cramping, heavy menses, and bleeding between periods. Although newer IUDs are better tolerated, women who have not borne a child have an increased risk of bleeding or cramping. Infections have been reported with IUD usage. The IUD itself does not cause an infection; however, if a woman is exposed to a sexually transmitted disease (STD), the presence of an IUD increases the risk of damage to pelvic organs. Thus, the IUD is a good choice for a woman in a stable, monogamous relationship and a poor choice for a woman with multiple partners or a partner who has multiple partners.
Reference: Human Reproduction