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Bayer Sued Over Alleged Hidden Risks of Mirena Contraceptive

Bayer AG was sued over claims the German drugmaker failed to provide disclosures and warnings regarding the health risks associated with its popular contraceptive Mirena.

The label for Mirena, an intrauterine device that prevents pregnancy for as long as five years, doesn’t warn that it can can become embedded in the body or cause an ectopic pregnancy, Pennsylvania resident Tricia Prendergast said in a complaint filed in federal court in Philadelphia. Prendergast required surgery to remove the device after complications, according to her complaint.

Bayer “introduced a product into the stream of commerce which is dangerous and unsafe in that the harm of Mirena use outweighs any benefit derived therefrom,” Dianne Nast, an attorney for Prendergast, wrote in the Jan. 25 complaint, which names Bayer’s U.S. unit, Bayer Healthcare Pharmaceuticals Inc.

Mirena, approved by the Food and Drug Administration in December 2000, is made of flexible plastic designed for insertion in the uterus, where it releases a synthetic progestogen that inhibits pregnancy, according to the complaint. More than 15 million women worldwide use the product, including more than 2 million in the U.S., Prendergast said in the complaint.

Side Effects

Bayer allegedly promoted the product as safe and effective “despite its lack of efficacy and potential for serious permanent side effects.” In addition to the risk of an ectopic pregancy -- one that occurs outside the womb -- Bayer failed to warn of complications that could require a hysterectomy, Prendergast claimed.

Prendergast is seeking unspecified compensatory and punitive damages.

“Bayer has not yet seen this suit but the company will vigorously defend itself against claims regarding Mirena,” Rosemarie Yancosek, a spokeswoman for Bayer Healthcare Pharmaceuticals, said in an e-mailed statement.

The case is Prendergast v. Bayer Pharmaceuticals Corp., 13-00450, U.S. District Court Eastern District of Pennsylvania (Philadelphia)

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