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female steroid sex hormone which prepares the uterus for child-bearing, 1935, from German Progesteron, from progestin (from which substance it was obtained), which had been coined 1930 from pro- (see pro-) + Latin gestare, literally "to carry about" (see gestation), on notion of "substance which favors gestation." Also see -one.
progesterone pro·ges·ter·one (prō-jěs'tə-rōn')
A steroid hormone secreted by the corpus luteum and by the placenta, that acts to prepare the uterus for implantation of the fertilized ovum, to maintain pregnancy, and to promote development of the mammary glands. Also called corpus luteum hormone, luteohormone, progestational hormone.
A drug prepared from natural or synthetic progesterone, used for the prevention of miscarriage and the treatment of menstrual disorders.