PROG levels are typically reported in units such as nanograms per milliliter (ng/mL) or nanomoles per liter (nmol/L). Progesterone levels fluctuate throughout the menstrual cycle and are essential for preparing the uterus for pregnancy and maintaining early pregnancy.

Measuring PROG levels can be helpful in assessing ovulation, evaluating fertility, and monitoring certain conditions related to hormonal imbalances, such as irregular menstrual cycles or infertility. In pregnant women, PROG levels can be used to monitor the health of the pregnancy.