It's one of the pillars of the pro-life argument: If life begins at conception and the morning-after pill prevents a fertilized egg from implanting in a woman's uterus -- as it says it does, right on the label -- then using emergency contraception like Plan B is tantamount to abortion.
But a closer look at a decade's worth of research shows that the morning-after pill doesn't actually work that way. Which means that one of biggest battles in the political war over women's reproductive health -- an idea that has sparked anti-abortion legislation around the country and outrage over President Obama's health care mandate -- is based entirely on outdated, incorrect data.
After sifting through the science, some of it more than 10 years old, The New York Times has found that the federally approved labels and medical authorities aren't telling patients what the research really shows: That emergency contraception pills delay ovulation and thicken cervical mucus (making it harder for sperm to reach their target), but do not stop an already-fertilized egg from implanting in the uterus.
"These medications are there to prevent or delay ovulation," Dr. Petra M. Casey, an obstetrician-gynecologist at the Mayo Clinic, told the New York Times. "They don't act after fertilization."
One cause of confusion may be that many abortion opponents think Plan B, the non-prescription morning-after pill, is the same as RU-486, the drug used to medically induce an abortion by destroying an implanted embryo. But ignorance is only part of the equation: The misinformation about preventing implantation appears on the Plan B label itself because the Food and Drug Administration insisted that it be included, in spite of the fact that there was no scientific proof of it at the time.
Their reasoning: The FDA was focused on whether the pill's active ingredient worked, not on how it worked, so they included all of the possible theories, whether they had been scientifically tested or not. FDA spokeswoman Erica Jefferson told the New York Times that confidentiality rules prevented her from discussing the details, but it can be difficult to define exactly how a drug works, even after it's been approved for use.
The National Institute of Health has since deleted the misinformation from its website, but when it comes to politics, morals, and long-held beliefs, proof sometimes isn't enough.
Pharmacists for Life International cites "FDA data" in a note that calls Plan B an "Emergency Abortion drug" and says "Rarely will a drug like Plan B work to suppress ovulation" -- a direct contradiction of what the FDA actually says online.
Dr. Donna Harrison, director of research for the American Association of Pro-life Obstetricians and Gynecologist, says that the studies of PlanB did not include enough women or documentation, and says that the active ingredient in morning-after pill Ella is similar to that of RU-486. (Experts point out that RU-486's ingredient is given "in a dose up to 20 times higher than Ella's ingredient and is taken when women are up to seven weeks pregnant, long after the egg has implanted," the New York Times reports.)
The FDA still hasn't agreed to revise labels for the morning-after pill, though a spokesperson acknowledged the new research seems accurate. And pro-life groups say that the research doesn't resolve their concerns.
"I would be relieved if it doesn't have this effect," Richard Doerflinger, associate director of the Secretariat of Pro-Life Activities for the United States Conference of Catholic Bishops, told the New York Times. "So far what I see is an unresolved debate and some studies on both sides… it's not only unresolved, but it may be unresolvable."
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