In February, the FDA said they would approve the sale of RU-486, also known as mifepristone, but subject to some final but undisclosed requirements.
"We are deeply concerned that the FDA is considering restrictions that in my view would virtually assure that very few doctors would ever make mifepristone available," Feldt said Tuesday.
She said the biggest concern is an FDA proposal that physicians allowed to administer RU-486 must be part of a registry, which she said would deter doctors worried about anti-abortion violence from offering the pill.
Feldt added that the FDA is also considering long-term health tracking of at least some RU-486 recipients, something she called unnecessary because half a million European women have used the pill successfully since 1988.
FDA officials declined comment.
But Sandra Waldman of the Population Council said although the FDA's recent proposals are more restrictive, the requirements are not yet complete.
Studies show RU-486 is 95.5 percent effective in causing abortion when taken within the first 49 days of pregnancy. But a very small percentage of patients required additional surgical treatment or blood transfusions, something the FDA must consider in determining how the pill should be used.
One question is how to ensure women return for an exam to be sure the pregnancy was terminated.
The nonprofit Population Council in 1994 received U.S. marketing rights to RU-486 from the original French manufacturer, which feared an anti-abortion boycott.
Planned Parenthood is a family planning group that favors abortion rights.
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