Last Updated: Tuesday, January 31, 2012.

Pfizer Inc., the pharmaceutical giant and world’s largest drug maker, is recalling 1 million packs of birth control pills in the United States, because they may not contain enough hormones to be effective enough to prevent pregnancy. The recalled birth control pills include:

• 14 lots of Lo-Ovral (28 day) Oral tablets
• 14 lots of Norgestrel and Ethinyl Estradiol (the generic form of Lo-Ovral)

Each pack of the birth control pills contains 21 white tablets, which contain synthetic hormones (Norgestrel and Ethinyl Estradiol), and 7 inactive pink pills. The affected birth control tablets have expiration dates that range between July 31, 2013 and March 31, 2014.

These 28-day oral contraceptives are being recalled after an investigative found that some of the blister packs of the birth control pills might contain an inexact count of active ingredients. In addition, some of the packets of birth control pills contain too many active (white) tablets, while the others had too few active tablets. As a result, this can make the birth control pills ineffective and put women at risk for getting pregnant.

The pills don’t pose an immediate health risk, but they can put you at risk for pregnancy. Pfizer recommends that any women with the recalled birth control pills stop using them and switch to a non-hormonal form of contraceptive right away.

The following are lot numbers of the affected packs of Lo-Ovral and its generic:

If you are using any of the recalled birth control pills and you experience negative/adverse reactions to the medication, you should contact Akrimax Medical at  1-877-509-3935 (8 AM to 7 PM Mon-Fri CST) or to FDA’s Med Watch Program.