A progesterone blood test is conducted to ascertain how much of the progesterone hormone is within a sample of blood. This female hormone is produced whenever a mature egg is released from an ovary within a process generally known as ovulation. This hormone helps to prepare the endometrium (uterine lining) to just accept the egg if sperm fertilizes it. If the egg goes without getting fertilized, menstrual bleeding occurs and progesterone levels drop. Reactive arthritis - this can cause inflammation of the joints, eyes and urethra (tube through which urine passes). Not long after infection of the gut and genital tract, or less frequently after throat infection. Rheumatic polymyalgia - a condition that almost always affects people over 50 years of age, in which case the immune system can cause muscle pain and stiffness, often across the shoulders and upper legs. It can also cause joint inflammation. 5. Exercise. This helps increase libido by stimulating your sex organs and circulating blood properly throughout the body. Devote a few minutes of your time to exercise daily.