Many regularly assume that Natural Family Planning, promoted by the Catholic Church, means the Rhythm method. But they couldn’t be further from the truth.

This happened again last week after Associated Press reporter David Crary reported on a Department of Health and Human Services (HHS) announcement outlining its “guidelines and priorities for the next round of Title X grant applications” that will compete for an estimated $260 million.

“The new HHS document makes repeated favorable mention of ‘natural family planning’ — which encompasses the rhythm method and other strategies for avoiding pregnancy without using contraceptives like the birth-control pill,” Crary wrote.

The HHS press office itself didn’t mention the Rhythm method. “The funding opportunity will assist in the establishment and/or operation of voluntary family planning projects,” the HHS press release read, “including information, education and counseling related to family planning, preconception care, contraception, natural family planning and infertility services.”

But another section of the HHS website does list the “Calendar Rhythm Method” as a “fertility awareness-based method” that falls under “natural family planning methods.” This was the section Crary must have drawn from.

The rest of the media followed suit. In reaction to the news, the media immediately used the terms Natural Family Planning and the Rhythm method interchangeably – without checking for differences.

“A new HHS doc favorably mentions ‘natural family planning’—which encompasses the rhythm method and other strategies for avoiding pregnancy without contraceptives,” repeated MSNBC producer Kyle Griffin on Twitter.

Maureen Shaw, published by outlets including NBC News and Teen Vogue, added, “‘natural family planning’ = unintended pregnancies = rise in need for abortion care.”

As the senior politics reporter for the Huffington Post, Laura Bassett chimed in, “There’s a word for people who rely on the rhythm method: ‘pregnant.’”

This isn’t the first time this has happened. Despite backlash from Natural Family Planning (NFP) users, Planned Parenthood President Cecile Richards has even repeatedly referred to the Rhythm method as NFP.

But the Catholic Church, perhaps the biggest proponent of NFP, says otherwise.

According to the United States Conference of Catholic Bishops (USCCB), “studies show that couples who follow their NFP method’s guidelines correctly, and all the time, achieve effectiveness rates of 97-99%.” The USCCB also argues that NFP is not “Rhythm,” which has been “often proved inaccurate.” Unlike the obsolete Rhythm method, NFP “take[s] account of a woman’s changing signs of fertility,” including by measuring temperatures.

And, in its instruction, the Catholic Church doesn’t stop there. It takes great pains to explain why it supports NFP instead of contraception.

The Catechism of the Catholic Church stresses that contraception prevents “giving oneself totally to the other” which “leads not only to a positive refusal to be open to life but also to a falsification of the inner truth of conjugal love.” And Pope Paul VI writes in Humanae Vitae that contraception translates into rising marital infidelity, lower moral standards and increased perception of women as “mere instrument[s] of selfish enjoyment.”

In other words, Church doctrine teaches that actively preventing conception or “every action which … proposes, whether as an end or as a means, to render procreation impossible” is “intrinsically evil.” “Periodic continence,” such as Natural Family Planning prescribes, is permitted because it “respect[s] the bodies of the spouses, encourage tenderness between them, and favor the education of an authentic freedom.”

That’s not something the media often report. But with more than one billion Catholics occupying the world (including the United States), let’s hope they take the time to research the differences.