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Progesterone is a steroidal hormone that plays a central role in the female reproductive cycle. The sex hormone is produced primarily by the adrenal glands, the placenta, and the corpus luteum of the ovaries. In the absence of oocyte fertilization during ovulation, natural progesterone levels in the blood serum decline, and menstruation begins. However, if the egg is fertilized, progesterone levels will increase to support the pregnancy, maintain the corpus luteum, and promote mammary gland development and milk production.

View a second image of progesterone.

Whether synthesized or extracted, progesterone features 21 carbons, 30 hydrogens, and 2 oxygen atoms per molecule and a molecular weight of 314.47. Known also by its chemical name, pregn-4-ene-3,20-dione, progesterone forms a white, odorless, crystalline powder or colorless crystals that are stable in air, practically insoluble in water, and soluble in organic solvents such as alcohol, acetone, and dioxane. The melting point for crystalline progesterone is between 126 and 131 degrees Celsius.

Naturally occurring progesterone aids glucose metabolism, and facilitates the formation of healthy bones. In additional, synthetic derivatives of this hormone are prescribed for birth control purposes, as well as to alleviate various difficulties associated with menopause. With hormone replacement therapy, progesterone (or progestins, as the synthetic forms are commonly called) helps reduce the risk of endometrial cancer inherent in estrogen therapy. However, blood clots, various cardiovascular disorders, and decreased high-density lipoprotein (HDL) levels have also been conditions associated with progestin administration. Prescribing the hormone in lower doses has reportedly helped reduce such risks while lowering the risk of osteoporosis.

Contributing Authors

Omar Alvarado, Thomas J. Fellers and Michael W. Davidson - National High Magnetic Field Laboratory, 1800 East Paul Dirac Dr., The Florida State University, Tallahassee, Florida, 32310.



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