George Cotsarelis, professor and chair of dermatology at the Perelman School of Medicine at the University of Pennsylvania, in Philadelphia, is skeptical of product claims.

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Koop was born in Brooklyn, New York, and attended Dartmouth, Weill Cornell Medical College and the Perelman School of Medicine at the University of Pennsylvania.

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Samantha Pfeifer, an associate professor of obstetrics and gynecology at the Perelman School of Medicine at the University of Pennsylvania, says the test is usually used to determine what dose of fertility medicine to use for IVF.

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