Qualitest Pharmaceuticals is voluntarily recalling several lots of birth control pills because of a packaging error that could leave women at risk for unplanned pregnancy, the U.S. Food and Drug Administration (FDA) said.

Select blisters were rotated 180 degrees within the card, reversing the weekly tablet orientation and making the lot number and expiration date no longer visible, the FDA said in a statement on its website.

The error means the daily regimen for the oral contraceptives may be incorrect and could leave women at risk of an unplanned pregnancy, it said. The defects do not pose any immediate health risks.

This packaging error and the potential for this error to have affected other oral contraceptive products resulted in the company issuing the recall of multiple lots, the agency said.

The recall takes effect immediately. It includes Cyclafem 7/7/7, Cyclafem 1/35, Emoquette, Gildess FE 1.5/30, Gildess FE 1/20, Orsythia, Previfem and Tri-Previfem.

The affected lot numbers can be found here

Qualitest is a unit of Endo Pharmaceuticals Holdings Inc.