Until recently, both the National Institute of Health and the Mayo Clinic, two respected and oft-Googled sites listed what science now considers misinformation regarding emergency contraception. It wasn't until the New York Times approached these organizations with an investigation based on previous (meaning not brand new) scientific studies, that these medical authorities removed faulty descriptions that said morning-after pills block these fertilized eggs from implanting in the uterus. But Pam Belluck's story explains that scientists have long known that this is not how morning-after pills work.

Two recent studies approved by the International Federation of Gynecology & Obstetrics and brought to our attention by Reality Check's Kelly Cleland have conclusively proved that emergency contraceptives were unable to prevent implantation. But science has been disproving this myth for awhile. This 2002 study found two popular emergency contraception drugs was due to inhibition of ovulation, not implantation. Another 2006 study had the following conclusion: "These data are supportive of the concept that the LNG ECP has little or no effect on postovulation events but is highly effective when taken before ovulation."

The erroneous descriptions have not only given women who might be interested in emergency contraceptionthe wrong idea about how the pill works, but the mislabeling has led the pro-life contingent, including Presidential candidate Mitt Romney, to associate these medications with the abortion debate. Not only is this information just wrong, but it's served as the pro-life justification for why government health care plans should not cover these so-called "abortion pills." The Food and Drug Administration still requires Plan B labeling include this reasoning. Such is the stuff of politics.

But having two major medical, rather than government, organizations perpetuate the unfounded notion of Plan B as an "abortion pill" doesn't give the correct science much of a chance to take root with the public. The N.I.H page comes up on the first page of Google searches for "emergency contraception" and "emergency contraception information," giving these groups an unfounded scientific credence. Plus, someone who might not believe in abortion but still need emergency contraception information could get the wrong idea about these pills from a major science institution. Now, at least when heading to the Times, Mayo Clinic or N.I.H, the most accurate, up-to-date scientific information is there.

Before the Times made its inquiry, the Medline Plus page, which acts as the National Institute of Health's information hub, had a line in there referencing this implantation issue, as you can see below from this July 2011 screengrab. Heading over to that page today, the word implantation does not exist. The Times uses the same content for its medical information and because of its own investigation updated its site, too.

The Mayo Clinic told Belluck it was "chomping at the bit" to revise its website. Heading over to the site, it does mention this implantation. But then it has the following disclaimer next to that point. "However, recent evidence strongly suggests that Plan B One-Step and Next Choice do not inhibit implantation." It's not clear if that is a new addition. But this June 2010 capture of the page had no such disclaimer.

In spite of all the research, however, the misinformation proliferates because of an archaic Food and Drug Administration ruling, as Belluck explains. "The implantation idea stems from the Food and Drug Administration’s decision during the drug-approval process to mention that possibility on the label — despite lack of scientific proof and objections by the manufacturer of Plan B, the pill on the market the longest," she writes. "Leading scientists say studies since then provide strong evidence that Plan B does not prevent implantation, and no proof that a newer type of pill, Ella, does," she continues. The F.D.A even acknowledged the research disproves the implantation theory. "The emerging data on Plan B suggest that it does not inhibit implantation. Less is known about Ella. However, some data suggest it also does not inhibit implantation," and F.D.A spokesperson told Belluck. Yet, the F.D.A would not discuss any plans to make any changes.