Measurement of progesterone in serum or plasma is considered to be the most reliable way to assess its rate of production. Progesterone is a steroid hormone, which plays an important role in the preparation for and maintenance of pregnancy. It is synthesized from cholesterol via pregnenolone – then rapidly metabolized to pregnanediol primarily in the liver. The ovary and placenta are the major production sites, but a small amount is also produced by the adrenal cortex in both men and women.

The Biorex Diagnostics Progesterone kit is a colorimetric enzyme-linked immunosorbent assay (ELISA) intended for the quantitative determination of progesterone concentration in human serum or plasma.