Vicki Saporta, president of the National Abortion Federation, says Health Canada has requested additional information from the drug's manufacturer, a request that will delay until next fall a decision on whether to approve mifepristone.
Once the manufacturer supplies that information, "Health Canada would undergo their normal review process of the additional information that's submitted," Saporta said in an interview with CBC News.
If approved, mifepristone would be available by prescription to terminate pregnancies of up to nine weeks. It's different from the morning-after pill, which is used within a few days after sex to prevent pregnancy.
Another drug, misoprostol, is used after mifepristone to complete the process.
Saporta said she's disappointed, but "very optimistic that at the end of the day, Health Canada will approve mifepristone as a safe and effective method of early abortion, and that Canadian women will then be able to use it with confidence that there has been a very thorough review of the medication, its safety and efficacy."
Health Canada has had the application to approve the drug, also known as RU-486, since December 2012. It usually takes about nine months for pharmaceuticals to work their way through the approval process, but a request for additional information resets the clock on the application.
If the drug were to be approved in the fall, it wouldn't hit the market until 2016.
Drug in use since 1988
Mifepristone was first approved for use in 1988 in France and has been used by millions of women in 57 countries, including the U.S., the U.K., in western Europe, Australia and New Zealand.
The National Abortion Federation says access to mifepristone doesn't increase the rate of abortion in a country, but changes the distribution of surgical versus medical terminations, reducing demand for surgery.
While there are no legal restrictions on terminating pregnancies in Canada, access to surgical abortion varies across Canada. There are no facilities on Prince Edward Island that terminate pregnancies, for example.
Approval of the drug would provide greater access to medical abortion for women in rural or remote parts of Canada.
"Having this pill approved, I think is really, really important to a lot of women who need to have access to reproductive choice. There shouldn't be any holdup as far as I'm concerned," New Democrat health critic Libby Davies said a year ago in an interview with CBC News.
Opponents, however, argue that the drug has caused several deaths in the U.S.
Mary Ellen Douglas, national organizer for the anti-abortion Campaign Life Coalition, told CBC News last year that she's concerned about reports of fatal sepsis.
"It's just not something that should be brought into Canada," Douglas said.
The U.S. Food and Drug Administration said in 2011 that sepsis is a risk related to any abortion and that it's not known whether using mifepristone and misoprostol caused those deaths.
"Reports of fatal sepsis in women undergoing medical abortion are very rare [approximately one in 100,000]," the FDA said in a fact sheet posted on its website.
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