The test measures blood Progesterone (P4) level. Progesterone is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species.
Progesterone is a type of steroid hormone present in both men and women. In women, the progesterone hormone is produced in the ovaries, the placenta (when woman is pregnant) and the adrenal glands. It stimulates and regulates important functions. It is involved in maintaining pregnancy, preparing the body for conception and regulating the monthly menstrual cycle. The level of progesterone increases sharply during the luteal phase of the menstrual cycle and during the period from 9 to 32 weeks of pregnancy. The progesterone is also a progestogen sex hormone playing a role in sexual desire.