As anyone who’s ever used an oral contraceptive knows, it’s important to take the pills in the right order, because each dose is different: Some pills contain hormones and some are inert and don’t do anything. Mixing those up could mean the difference between remaining unpregnant and getting pregnant. To prevent the latter, the maker of one birth control product is recalling pills that are packaged incorrectly.

Lupin Pharmaceuticals is recalling one lot of Mibelas 24 Fe (Norethindrone Acetate and Ethinyl Estradiol 1 mg/0.02 mg chewable and ferrous fumarate 75 mg) tablets.

They’re packaged in blister packs containing 28 tablets: 24 white to off-white tablets of active ingredients debossed with “LU” on one side and “N81” on the other; and 4 tablets of inert ingredients debossed with “LU” on one side and “M22” on the other side.

The pills were distributed nationwide in the U.S. to wholesalers, clinics and retail pharmacies.

The recall was prompted by a consumer complaint about the error, in which the blister pack has been rotated 180 degrees, reversing the weekly tablet orientation.

“The reversing the order may not be apparent to either new users or previous users of the product, increasing the likelihood of taking the tablets out of order,” the Food and Drug Administration said.

This means you’d be taking the four placebo pills in the first week instead of the fourth, which could have big implications.

“As a result of this packaging error, oral contraceptive tablets that are taken out of sequence may place the user at risk for contraceptive failure and unintended pregnancy,” notes the FDA.

If you have the affected product, notify your doctor and return it to the pharmacy or place of purchase. Questions? call Lupin at 1-800-399-2561, 8 a.m. to 5 p.m. EST, Monday through Friday.

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