MADISON, N.J. (AP) — Allergan is voluntarily recalling packs of its birth control pills in the U.S. because of a packaging error with placebos, increasing the possibility of unintended pregnancy.

The company says four placebo pills were placed out of order in the Taytulla packs. Allergan says the first four days of therapy had four non-hormonal placebo capsules instead of active capsules.

The recall involves lot 5620706, which expires in May 2019. Consumers who have those birth control pills should arrange to return them to their physicians.

Consumers with questions about the recall are being asked to contact Allergan at 800-678-1605, Monday through Friday.