Progesterone is an endogenous steroid hormone involved in various stages of menstrual cycle, pregnancy, and embryogenesis of humans. It is the main hormone of luteal phase and is involved in priming the uterus for implantation of embryo and subsequently maintaining the pregnancy. Corpus luteum is the main source of progesterone secretion in the luteal phase and polyembryonic phase. With the advent of a RTE the role of progesterone supplementation at various stages has been evaluated constantly. The course gives a detailed insight regarding the role of progesterone at various phases of ART, ROLE OF TESTING AND SUPPLEMENTATION OF PROGESTERONE IN ENHANCING THE SUCCESS RATE OF IT PROCEDURES.