A pharmaceutical company is recalling birth control pills mislabeled in a way that could result in an unplanned pregnancy.

The pills, sold under the name Mibelas 24 F-E, were packaged in the wrong order so the first four days of tablets labeled as active pills are actually placebos.

The pills were distributed nationally.

If taken as labeled, consumers will not be receiving the right hormones to prevent conception and could end up pregnant, according to a statement released by the Food and Drug Administration.

The lot number affected is L600518 with an expiration date of May 2018, although, in addition to placing the pills in the wrong order, the packaging error also made the lot number and expiration date “no longer visible.”

Any consumers who have taken the mislabeled pills are advised to call their doctor immediately. The pills should be returned to the pharmacy.

Consumers with questions can call the manufacturer, Lupin Pharmaceuticals, at 800-399-2561.