2-Hydroxyestrone, Urine Creatinine Ratio Unit Converter

2-Hydroxyestrone (2-OH-E1) is a metabolite of estrone produced during Phase I estrogen metabolism in the liver. When the body breaks down estrone, it follows one of three main pathways: 2-hydroxylation, 4-hydroxylation, or 16α-hydroxylation. The 2-hydroxylation pathway produces 2-OH-E1 and is generally considered the most favorable of the three.

2-OH-E1 has weak estrogenic activity compared to its parent hormone. It is sometimes referred to as a "protective" estrogen metabolite because of its reduced ability to stimulate cell growth.

This test measures 2-OH-E1 levels in a urine sample, normalized to creatinine to account for differences in urine concentration. It is commonly included in comprehensive hormone panels such as the DUTCH test.

2-Hydroxyestrone is produced primarily in the liver through the action of CYP1A1 and CYP1A2 enzymes, which hydroxylate estrone at the 2-position. Smaller amounts may be produced in other tissues that express these enzymes.