What is Progesterone (LC-MS dried blood spot)?
Progesterone is secreted by the corpus luteum after ovulation, preparing the endometrium for implantation and maintaining early pregnancy until placental production begins. In the absence of ovulation progesterone remains low. Small amounts are produced by the adrenal cortex in both sexes. Dried blood spot progesterone equilibrates from the circulating pool and is quantified by LC-MS to avoid the cross-reactivity that plagues immunoassays of related steroids.