And also all of a sudden, such as a bolt from your blue, occurs precisely what almost any guy would choose to experience only inside a bad dream and not from the realism. A progesterone blood test is done to find out how much of the progesterone hormone is in a sample of blood. This female hormone is produced each time a mature egg is released from an ovary after a process referred to as ovulation. This hormone really helps to prepare the endometrium (uterine lining) to take the egg if sperm fertilizes it. If the egg goes without being fertilized, menstrual bleeding occurs and progesterone levels drop. The primary sex organs inside female would be the ovaries. Ovaries produce the eggs (ova) and secrete sex hormones. These hormones are needed to build up secondary sexual characteristics and results in cyclic changes in the secondary sex organs which can be required for reproductive function.