Apotex is recalling 11 more lots of birth control pills as a precautionary measure, Health Canada announced Friday.

"The company will be recalling additional lots of Alysena-28 birth control pills as a precautionary measure while it investigates why one lot of the product contained packages with extra placebo pills in place of active pills," Health Canada said in a news release.

Packages of Alysena-28 should have three rows of pink active pills and only one row of white placebo pills, Health Canada said.

The recalled packages: LF01901A LF01980A LF02037A LF01900A LF01982A LF02036A LF01898A LF01981A LF02026A LF01894B LF01979A

Although Alysena-21 is not part of the current recall, Health Canada encouraged Canadians to check to make sure their packages of that product contain three rows of pink pills.

Meanwhile, Canada's obstetricians and gynecologists said the recall of the potentially faulty birth control pills is unprecedented in its damage to women.

"I am concerned that Canadians may not have received important information in a timely manner," Health Minister Leona Aglukkaq said in a statement following a recall of one batch of the Alysena-28 that may contain two weeks of placebo sugar pills instead of one.

One batch of Alysena-28 birth control pills contained an extra week of placebo sugar pills. ((CBC))

The error can reduce the effectiveness of the pills, and raises the possibility of unplanned pregnancy if backups like condoms aren't used.

"I have instructed Health Canada to look into the issue and assess whether processes were followed and that they are sufficient," Aglukkaq said.

But the recall itself and how it was handled undermine women's confidence, says Dr. Jennifer Blake, CEO of Society of Obstetricians and Gynaecologists of Canada.

"This is just an unprecedented crack in the rock solid reliability that we've always enjoyed," Blake said in an interview Friday.

Last week's original recall notice from Apotex, the Canadian drug distributor of Alysena, only went to pharmacists, Blake said.

The delay until Health Canada notified women, physicians and medical professional societies was long enough to cancel effective use of morning-after protection. By the time the notice came out broadly, it would have been too late for many women to use that option, SOGC said.

Blake has four main concerns, including that:

The quality control was not sufficiently rigorous.

Women are being substituted with generic birth control without their knowledge.

There are products on the market that look alike and sound alike, "so that women genuinely might not know what they're taking."

There was "a really inexplicable delay in informing women, so that they could take immediate action."

The society is drafting a letter sharing its concerns with Health Canada.

Blossom Leung, a media relations officer at Health Canada, said the department regularly reviews its actions.

"As well, Health Canada will be following up with the company to ensure that the recall was initiated properly and will follow up to ensure that good manufacturing practices are followed," Leung said in an email.