Women with recalled packets are at greater risk of pregnancy and should use back-up contraception. Is your pill on the list?

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About 1 million packets of birth control pills are being recalled in the U.S. by Pfizer because a packaging mishap could increase the likelihood of pregnancy.

The affected pills include 14 lots of Lo/Ovral-28 tablets and 14 lots of generic Norgestrel and Ethinyl Estradiol tablets. All the pills were marketed by Akrimax Rx Products and have expiration dates ranging from July 31, 2013, to March 31, 2014. They were distributed to warehouses, clinics and pharmacies throughout the U.S.

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Birth control pills typically contain 21 days of hormone-laden, or active, tablets and 7 days of placebo pills. But some of the recalled packets have too many active tablets while others don’t have enough, and some of the pills may be out of sequence.

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The problem, which has since been corrected, seems to have been caused by inspection failures. “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,” Pfizer said in a statement released Tuesday. “…Consumers exposed to affected packaging should begin using a non-hormonal form of contraception immediately.”

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This is the second major contraceptive recall in less than six months. In September, Qualitest Pharmaceuticals recalled 1.4 million packages of birth control pills because of a different packaging error.

Women who have the recalled Pfizer tablets should contact their doctors and return the medication.

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According to the statement:

Any adverse events that may be related to the use of these products should be reported to Akrimax Medical Information at 1-877-509-3935 (8 AM to 7 PM Mon-Fri CST) or to FDA’s Med Watch Program.

Lot numbers of affected packs of Lo/Ovral-28 (norgestrel and ethinyl estradiol) Tablets and Norgestrel and Ethinyl Estradiol Tablets (generic) are reprinted here: