I had this test done to see if I had elevated 4-hydroxy estrogen metabolites. I have an upregulated CYP1B1 which metabolizes estrogens down the 4-hydroxy pathway which results in quinones which produce oxidative stress, as opposed to the 2-hydroxy pathway which does not produce the oxidative stress. A great diagram of this produced by Rich V is shown in the xeno-estrogens thread started by Gestalt. My results are: 2-hydroxyestrone (2-OHE1) 10.9 (.2-25.9) 2-hydroxyestradiol (2-OHE2) 3.3 (.1-11.3) 4-hydroxyestrone (4-OHE1) .7 (<=3.2) 16a-hydroxyestrone (16a-OHE1) 12.8 (.2-14.2) 2-methoxyestrone (2-OMeE1) .8 (.1-6.4) 4-methoxyestrone (4-OMeE1) <.23 (<=.3) To my great surprise the 4-hydroxyestrone was not elevated. What I"d really like to know and I'm hoping Rich is reading this - is since the CYP1B1 which converts estrogens into the 4-hydroxy type also is the enzymes that creates quinones - could an upregulation result in normal 4-hydroxy because it is being metabolized to quinones quickly ?