Can 19-nortestosterone derivatives be aromatized in the liver of adult humans? Are there clinical implications?

@article{Kuhl2007Can1D,
  title={Can 19-nortestosterone derivatives be aromatized in the liver of adult humans? Are there clinical implications?},
  author={Herbert Kuhl and Inka Wiegratz},
  journal={Climacteric},
  year={2007},
  volume={10},
  pages={344 - 353}
}
Context Previous studies in postmenopausal women have demonstrated that, after oral administration of norethisterone, a small proportion of the compound is rapidly converted into ethinylestradiol. The shape of the concentration – time curve suggested that this occurred in the liver. The results were confirmed by in vitro investigations with adult human liver tissue. In 2002, it was shown that, after oral treatment of women with tibolone, aromatization of the compound occurred, resulting in the… Expand
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Tibolone is not converted by human aromatase to 7α-methyl-17α-ethynylestradiol (7α-MEE): Analyses with sensitive bioassays for estrogens and androgens and with LC-MSMS
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