The FDA has put off deciding whether to allow over-the-counter sales of the Plan B "morning after" pill.

The problem isn't safety, says FDA Commissioner Lester Crawford, DVM, PhD. The agency is convinced the emergency contraceptive is safe for all women.

The problem, Crawford says, is that the FDA isn't convinced that women under the age of 17 can understand the product's instructions for use. That's why last year it rejected the full over-the-counter status requested by manufacturer Barr Pharmaceuticals.

Following that May 2004 refusal, Barr asked the FDA to approve Plan B for over-the-counter sale to women 16 and older. But the long-awaited decision on that request -- expected by the end of this month -- is once again on hold.

The main problem, Crawford said in a news conference, is how the FDA can enforce a rule restricting over-the-counter sale of Plan B to women 17 and older (the agency decided to up the age limit requested by Barr).

"There are unique regulatory issues that need to be addressed," Crawford said in a news conference. "We can only decide these issues in an open process. That will let us decide whether FDA can approve a drug for both over-the-counter and prescription use, for the same indication, sold in the same package."

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Open for Public Comment

The FDA is opening a 60-day public comment period -- shorter than its usual 90- and 120-day comment periods. But Crawford would not commit to a timetable for making a decision after that period is over.

"I make the commitment we will ... ensure this process is expeditious and thorough," Crawford said. "Expediting this process will be a personal priority of mine."

In a statement, Barr expressed regret at the FDA's lack of action.

"We are disappointed that the FDA did not approve our application," Barr CEO Bruce L. Downey says in a news release. "While we believe that a delay is not justified, we will use the opportunity presented by the FDA proceedings to continue to press for approval of Plan B as an over-the-counter/prescription product."

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What Plan B Is and Isn't

Plan B is an emergency contraceptive. That means it's supposed to be used only as a backup plan when a couple has unplanned sex or when other contraceptive methods fail.

Plan B is one of two approved emergency contraceptives. The other is Preven from Gynetics Inc. Gynetics has not asked for over-the-counter status, so today's FDA action -- or inaction -- applies only to Plan B.

Other contraceptives work by keeping a man's sperm from fertilizing a woman's egg. Depending on where a woman is in her menstrual cycle, emergency contraception may work the same way. But it is more likely to work after sperm fertilizes the egg.

Plan B helps keep a fertilized egg from implanting in a woman's womb. If Plan B fails and the egg implants, pregnancy proceeds normally.

Earlier this month, David M. Plourd, MD, told WebMD that Plan B is about 75% effective at preventing pregnancy after unprotected intercourse. Plourd is assistant professor of obstetrics and gynecology at Naval Medical Center in San Diego.

"Preventing pregnancy 75% of the time is less than almost every other form of contraception," Plourd said. "That is why it is plan B, not plan A."

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By Daniel J. DeNoon, reviewed by Michael W. Smith, MD

SOURCES: FDA news conference with FDA Commissioner Lester Crawford, DVM, PhD. FDA. News release, Barr Laboratories. WebMD Medical News: "FDA to Decide Status of Morning-After Pill." David M. Plourd, MD, assistant professor of obstetrics and gynecology at Naval Medical Center, San Diego.