IUDs, implants more reliable than birth control pills

While birth control pills are the most commonly used reversible contraceptive in the United States, a new study has found that women who use the pill are actually 20 times more likely to have an unintended pregnancy than women who use longer-acting birth control methods such as intrauterine devices (IUD) or hormonal implants.

The study, published in the New England Journal of Medicine, was conducted over a period of three years. It involved more than  7,500 sexually active women between the ages of 14 and 45, who did not want to become pregnant within the next 12 months.  The women were either not using birth control or were planning to switch birth control methods.

The researchers counseled the women on their birth control options, which included IUDs, implants, pills, patches, rings and injections, then followed up with the women every six months through the remainder of the study.  Participants who became pregnant during the study were asked if the pregnancy was intended and what contraceptive method they were using, if any, at the time.

During the course of the study, 334 of the women became pregnant, and 156 of the pregnancies were due to contraceptive failure.  Out of those women, 133 (4.5 percent) of the women had been using pills, the patch or ring at the time, compared to 21 women (.27 percent) who had been using IUDS or implants.

For women under 21, the discrepancy was even more pronounced: Adolescents and young adults who used birth control pills, the patch or ring had almost double the risk of having an unplanned pregnancy than older women in the study.

Dr. Jeffery Peipert, senior author of the study, and Robert Terry, professor of obstetrics and gynecology at the University of Washington, told FoxNews.com the study results called for a shift in the way doctors and patients consider and discuss birth control options, and in particular, IUDs – which had less than a 1 percent failure rate in the study but are only chosen by 5.5 percent of women in the U.S.

“When patients talk to their doctors about birth control, their first concern is always efficacy,” Peipert said.  “So why don’t we offer the most effective methods first? And if they choose not to have the most effective method [IUDs, implants], then move to second tier methods like the birth control pill, patch and ring.”

While all the birth control methods in the study boasted a 98 to 99 percent effectiveness in preventing pregnancy, the shorter-acting methods are often subject to ‘user error,’ such as forgetting to take pills, which can greatly reduce their effectiveness, Peipert said.

“The pill is 99 percent effective as long as you remember to take it every day, which to me, it’s ridiculous to talk about a ‘perfect’ user rate because that’s not real life,” Peipert said.  “In real life, there is user error.  The longer-acting methods remove that error.  Once they’re in place, you can forget about them.”

Meanwhile, according to Peipert, there are important ramifications to missing the pill as little as once or twice – and nearly 25 percent of women miss two or more pills a month.

“That’s a lot,” he said. “Depending on when the pills are missed in the cycle, it can make a difference as to whether or not a woman makes an egg or ovulates.”

Though IUDs and implants have a much lower failure rate, Peipert said there are three main barriers keeping women from pursuing these forms of birth control: knowledge, cost of the procedure -- which can be upward of $500 -- and access to clinicians who will perform the procedure.

He added it was also important to dispel certain myths surrounding IUDs, such as the beliefs that they can cause infertility or infections or that they do not work well for women who have already had children – all of which are untrue, according to Peipert.

Approximately 3 million – or 50 percent – of pregnancies each year are unplanned in the U.S.  The rate of unintended pregnancies is much higher than other developed nations, such as France, which have a higher rate of IUD or implant usage.

“My hope is that some people will say this study will be a game-changer shift in the U.S. to more effective methods,” Peipert said.  “Unintended pregnancy is a costly health problem in this country.  One dollar invested in family planning can save $3 to $4 down the road.”