17α-Hydroxyprogesterone (Standard) is the standard substance of 17α-Hydroxyprogesterone, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. 17α-Hydroxyprogesterone (17-OHP) is a physiological progestin that is produced during glucocorticoid and steroid hormone synthesis and is increased during the third trimester of pregnancy. Hydroxyprogesterone binds to the cytoplasmic progesterone receptors in the reproductive system and subsequently activates progesterone receptor-mediated gene expression.