The vast majority of women in the U.S. are not using the most effective method of birth control available, according to a new study from the Washington University School of Medicine in St. Louis.

The study finds that the pill is significantly less effective at preventing pregnancy than long-lasting contraceptive methods such as the intrauterine device (IUD), building on earlier research that has drawn the same conclusion. In fact, women using IUDs or implants were a staggering 20 times less likely to get pregnant than women who used shorter contraceptive methods like the pill.

Yet few women in the U.S. currently use this type of contraception because IUDs are often very expensive — with co-pays costing hundreds of dollars — and rarely covered by insurance plans. As the study’s lead author, Dr. Brooke Winner, told Reuters:

Nationally, only about 5 percent are using long-lasting methods like IUDs and implants. We know one of the barriers to why they’re not using them more frequently is up-front costs. If [more] women were using these products nationally, there would be a very significant drop in unintended pregnancies, which would have far-reaching effects.

Although the birth control pill is the most commonly used contraceptive in the U.S., its effectiveness diminishes when women miss any of their daily pills or struggle to fill their monthly prescriptions on time. So if IUDs are significantly more effective at preventing pregnancy than the pill, doctors ought to be encouraging more women to use them. As another one of the study’s authors points out, “If there were a drug for cancer, heart disease or diabetes that was 20 times more effective we would recommend it first.”

Fortunately, President Obama’s new birth control regulation that expands access to birth control may help both doctors and women address this issue. Because the new policy would eliminate co-pays for contraceptives, IUDs would become a viable option for the women who currently can’t afford them — and, as the Guttmacher Institute has documented, removing cost barriers to contraceptive services greatly increases the number of women who choose to use the most effective methods.

Earlier this year, presumptive GOP presidential nominee Mitt Romney came out strongly against the Obama administration policy that will require health insurance plans to offer birth control coverage at no additional cost — one of the many important preventive health benefits women will receive as a result of Obamacare.

In particular, Romney denounced the fact that insurance plans would now be required to cover Plan B, a form of emergency contraception that he falsely referred to on numerous occasions as “abortive pills.” This is what Romney said in Colorado on February 6, 2012:

ROMNEY: This same administration said that the churches and the institutions they run, such as schools and let’s say adoption agencies, hospitals, that they have to provide for their employees free of charge, contraceptives, morning after pills, in other words abortive pills, and the like at no cost. Think what that does to people in faiths that do not share those views. This is a violation of conscience.

(Plan B works just like regular birth control pills and is not, in fact, an abortifacient.)

The Miami Herald’s Marc Caputo reports that next week the Romney campaign will be doing a major fundraising blitz across Florida, including an event “at the Star Island manse of pharmaceutical magnate Phil and Pat Frost where dinner costs $50,000.”

Who is Dr. Phil Frost? He is the Chairman of the Board of Directors of Teva Pharmaceuticals, a major manufacturer of contraceptives. Its North American website prominently advertises several forms of contraception, including Plan B One Step, which Romney previously denounced as an “abortive pill”:

This isn’t Romney’s first instance of hypocrisy on this issue.  Earlier this year, ThinkProgress revealed Romney’s hypocrisy, noting that he was financially invested in — and profiting from — the very products he was seeking to restrict affordable access to:

Romney’s Goldman Sachs 2002 Exchange Place Fund, valued at over a million dollars in 2010, brought in nearly $600,000 in gains in 2010 and is invested in:

- Watson Pharmaceuticals: manufacturer of nine forms of emergency contraception (which Romney incorrectly identifies as “abortifacients“).
- Johnson & Johnson: launched the first U.S. prescription birth control product in 1931 and produces various forms of birth control.
- Merck: produces various forms of birth control
- Mylan: produces birth control medication and filed the first application for a generic birth control pill last year.
- Pfizer: a contraception producer that recently had to recall about a million packs of birth-control pills that weren’t packaged correctly.

It appears that Mitt Romney strongly opposes emergency contraception, except when it’s of financial benefit to him or his campaign.

Since the Obama administration promulgated a new rule requiring employers and insurers to provide preventive health care services — including contraception coverage — some Catholic institutions have taken great offense to the regulation and accused the White House of waging a war against their religious objection to birth control. The rule exempts religious institutions and affiliated organizations from providing the benefit and offers employers a year-long grace period to implement the measure.

And while some Catholic colleges have responded to the controversy by stripping contraception from their plans, Georgetown University — the nation’s first Catholic institution of higher learning — has announced that it will not adopt any changes to its health insurance policies and will continue to provide birth control coverage to its employees. In a letter obtained by ThinkProgress dated April 26, 2012, President John J. DeGioia informs the Georgetown community that the University will offer contraception “for students who require them for health reasons unrelated to birth control,” and will institute “no change to the University’s approach to contraceptive coverage for employees”:

After thoughtful and careful consideration, we will continue our current practice for contraceptive coverage in our student health insurance for the coming year, as allowed for under the current rules issued by the United States Department of Health and Human Services.

There will also be no change to the University’s approach to contraceptive coverage for employees for 2013.

We will be monitoring further regulatory and judicial developments related to the Affordable Care Act. I hope this is helpful in clarifying a matter of concern to many of you.

In February, a Georgetown University spokesperson confirmed to ThinkProgress that employees “have access to health insurance plans offered and designed by national providers to a national pool. These plans include coverage for birth control.”

Twenty-eight states already require organizations that offer prescription insurance to cover contraception — including some of the nation’s largest Catholic institutions.

Republicans have been taking a curious tack in defending accusations of their “war on women.” Instead of arguing flat-out that their women’s health policies are beneficial to, or supported by, women, they argue that women won’t vote on issues such as contraception. Therefore, they’ve concluded, their views on women’s health won’t matter.

South Carolina Governor Nikki Haley (R) went on The View early this week arguing that “women don’t care about contraception.” And on Wednesday, in his speech to the American Society of Newspaper Editors, presidential candidate Mitt Romney said:

In the final analysis I will win by having the support of men and women, in the battleground states and across the country. That will be by focusing on the issues that women and men care most about. My wife has the occasion to campaign on her own and also with me, and she reports to me regularly that the issue women care about most is the economy, and getting good jobs for their kids and for themselves. They are concerned about gasoline prices, the cost of getting to and from work, taking their kids to school, or to practice and so forth.

It’s telling that the Republicans won’t stand up for their views on contraception — which they want to severely limit or eliminate. But polling and analysis show that women will indeed vote on women’s health issues. In fact, according to a recent Gallup poll of swing state voters, “women voters, by a 20-percentage-point margin, 55% to 35%, are significantly more likely than men to rate government policies relating to birth control as important.” This same poll pointed to a female-driven bump in favor of President Obama.

But moreover, women’s health issues affect each of the categories that Republicans have deemed (and, yes, polls have confirmed) will define the election: Health care, the economy, and the federal budget/national debt are all in some way tied to that “retro debate” on women’s health.

Contraception affects each of those categories– and here’s how:

Contraception is good for the economy. Access to contraceptives has afforded women the opportunity to hold off on having children until they’re ready, giving them a chance to have a career. Subsequently, the American economy has grown by 25 percent: Women held 37 percent of all jobs in 1979– they now hold almost half. And it’s not over. According to the Bureau of Labor Statistics, women are “projected to account for 51 percent of the increase in total labor force growth between 2008 and 2018.”

Access to contraceptives has helped women make more money. Contraceptives help grow women’s wages, and bring us closer to pay equality. The gender pay gap shrunk significantly — by 30 percent — because of the pill. While it’s still not up to snuff, denial of access to contraceptives wouldn’t help the pay gap close. Add to that the expense of birth control, and women’s wallets could be a lot lighter.

Birth control saves taxpayers money and reduces America’s debt. A Brookings report “estimate[s] that taxpayer spending on Medicaid-subsidized medical care related to unintended pregnancy totals more than $12 billion annually.” By decreasing unplanned pregnancies, there are fewer mothers who look to the government for assistance.

Contraception is health care. Women strongly consider health care one of the most important political issues, so then it’s only natural that contraception should be too. Access to contraception not only controls cost of women’s health care by reducing the number of unintended pregnancies, it is used as a medication for ovarian cysts, certain types of cancer, early menopause, severe acne, extreme cramps, and many other health complications women face.

Mitt Romney found himself in hot water over his opposition to expanding women’s access to contraception, less than a week after suggesting that he would “get rid of” Planned Parenthood, among other programs, to reduce the deficit. During a town hall in Illinois Monday evening, the former Massachusetts governor told a voter to “vote for the other guy” if she wanted access to “free birth control” and said that the federal government should not subsidize women’s health care through Planned Parenthood:

Q: I’m just wondering where you would suggest that the millions of women who receive their health services, such as mammograms, and HPV vaccines go?

ROMNEY: Well, they could go wherever they’d like to go — this is a free society. But here is what I say, which is the federal government should not tax these people to pay for Planned Parenthood. There are a lot of things that we have in our society that we may like, that we might not like, but that government should not be paying for.

Watch it:

Despite expanding health care to women as governor of Massachusetts — and even attending a Planned Parenthood fundraiser in 1994 as a Senate candidate — Romney has come out against helping women find affordable reproductive health services since announcing his presidential candidacy.

Beyond simply threatening Planned Parenthood, which provides necessary health care for millions of women, Romney has also called for cutting funds for Title X — the only federal program devoted to family planning — from the federal budget. He endorsed the so-called Blunt amendment to allow any employer to drop health insurance coverage for contraception and other health services on moral grounds, and spoke out against requiring employers and insurers to provide birth control coverage in their health care plans at no additional cost. Given that track record, many women and health advocates may indeed be inclined to “vote for the other guy.”