The U.S. abortion rate is at its lowest since the year the Supreme Court legalized the procedure nationwide.

Why? Well, greater use of and access to long-acting birth control, a new study has found.

It would seem to be obvious: Increasing access to contraception results in fewer unintended pregnancies and fewer abortions. It’s a win for everyone. Opponents of abortion, however, have been happy to link the nationwide decline in terminated pregnancies to continuing efforts to restrict abortion — even though there’s likely no relationship between the two.

So it’s up to the rest of us to look at the facts, stand firm against efforts to restrict a safe and legal procedure, and stand up for publicly funded family planning services.

Between 2008 and 2011 — the latest year for which figures were available — the United States saw a decline in both the abortion rate (16.9 per 1,000 women ages 15 to 44) and the number of abortions (about 1.1 million). The abortion rate hasn’t been any lower since the 1973 Roe v. Wade ruling, according to the Guttmacher Institute, a reproductive health think tank.

During the same time period, states implemented more than 100 laws intended to restrict access to abortion. But while the new restrictions affected mostly Midwestern and Southern states, the incidence of abortion fell across the country. And states with liberal abortion laws, such as California and Oregon, saw “declines in their abortion rates comparable to, and sometimes greater than, the national decline” of 13 percent, the Guttmacher Institute found. This accords with the experience in Maine — long a center of pro-reproductive rights activity — where the drop in the abortion rate from 2008 to 2011 was 12 percent.

Affordable, accessible, effective birth control has been a major factor in this decline. More women have embraced long-term reversible contraception, such as the IUD, which can work for up to 10 years once inserted into the uterus, or hormone implants inserted under the skin of the arm, which are effective for three years.

What’s more, Guttmacher researchers found, use of these more-effective methods has jumped among women who use publicly funded clinics.

Since unintended pregnancy rates are highest among low-income women, anything that makes long-acting birth control more affordable could affect abortion rates. That includes the Affordable Care Act mandate that contraceptives be covered by all health-care plans, which has encountered much resistance from religious groups.

On the state level, we should monitor Maine’s funding for family planning services. State budget cuts in 2012 forced 12 rural family planning clinics to reduce their hours, thus limiting their accessibility to clients.

Everyone has reason to support access to contraception, regardless of their feelings about abortion. In fact, 89 percent of all U.S. adults believe that contraception is morally acceptable, Gallup has found.

So let’s focus on what unites us, rather than what divides us, by making women’s lives better by making it easier for them to get birth control.