Progesterone occurrence

Ellis DL, Wheeland RG, Solomon H. Estrogen and progesterone receptors in melanocytic lesions. Occurrence in patients with dysplastic nevus syndrome. Arch Dermatol 1985 121(10) 1282—5. 

Pharmacodynamics Serum progesterone and 17-P-estradiol levels are considered reliable indicators for the occurrence of ovulation. Since progesterone and 17-f)-cstradiol levels were comparable for both treatments, and progesterone serum concentrations did not exceed 1.4 ng/mL (as defined in this study, progesterone concentrations above 1.4 ng/mL on day 20 of a menstrual cycle indicated ovulation) for both treatments, it was concluded that Drug XYZ administration did not affect the contraceptive effect of ethinylestradiol-based oral contraceptives and that no ovulation occurred in any of the subjects. 

The HPG axis is responsible for the cyclic hormone secretion that regulates and controls ovulation and plays a major role in menstruation-related disorders. The menstrual cycle is characterized by cyclic alterations in the production of gonadal hormones (estradiol and progesterone), pituitary hormones (gonadatropins, prolactin, growth hormone), melatonin, and cortisol and in temperature rhythms. Menstruation-related disorders are likely the result of a complex interaction between ovarian steroids and central neurotransmitters, neurohormones, and neuropeptides. The occurrence of physical... 

Due to the common occurrence of steroids in Nature, there is not much need to synthesize the steroid skeleton from simple substrates. Therefore, the use of phosphonates in syntheses involving this class of compounds, concerns mostly modifications of the steroid pool, like in the case of the conversion of 17-oxo-steroids to 20-ketosteroids and progesterone as well as construction of the South steroid subunit of cephalostatin 1 from hecogenin acetate. 

Warrier, S.R., Tirumalai, R., and Subramoniam, T. (2001) Occurrence of vertebrate steroids, estradiol 17 3 and progesterone in the reproducing females of the mud crab Scylla serrata. Comp. Biochem. Physiol, 130A, 283-294. 

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