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Progesterone (pregn-4-ene-3,20-dione; abbreviated as P4) is an endogenous steroid hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species.
Added 7/12/2014 1:26:58 PM
This answer has been confirmed as correct and helpful.
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yumdrea [7/12/2014 1:46:48 PM]