Progesterone is a hormone. In addition to its role in helping to regulate menstrual cycles, preparing the uterus for pregnancy, and helping to maintain a pregnancy, progesterone has many roles in the body. These include breast development and function, sex drive, brain functioning, pancreatic function, gum health, body temperature, and studies have shown that women and men who have higher levels of progesterone may have more homoerotic feelings than people whose levels of progesterone are closer to average. Progesterone is produced by the ovaries, the placenta, and the adrenal glands.