World's largest pharmaceutical company, Pfizer, recalled over 1 million packs of its birth control pills in the United States after they discovered a packaging error, possibly putting women at the risk of unintended pregnancies.

The package apparently contains inadequate dose of hormonal-based drugs that might not prevent pregnancy and women on contraceptive could still be pregnant.

The company has recalled 14 lots of Lo/Ovral (28 tablets) and 14 lots of Norgestrel and Ethinyl Estradiol tablets.

As a result of this packaging error, the daily regimen for these oral contraceptives may be incorrect and could leave women without adequate contraception, and at risk for unintended pregnancy, the company said in a statement on its Web site.

According to Pfizer, the pills have no health thread to women and the error is identified and corrected immediately.

It doesn't pose immediate health risks, however, consumers exposed to affected packaging should begin using a non-hormonal form of contraception immediately, company said in a statement.

The drug packages were distributed to warehouses, clinics and retail pharmacies throughout the U.S. and have an expiry dates ranging between July 31, 2013 to March 31, 2014, the company said.

The oral birth control pills were manufactured by Pfizer and marketed under Akrimax Pharmaceuticals brand.