If you have a progesterone deficiency, it can cause some uncomfortable problems and make you infertile. The levels of progesterone will rise and fall dramatically during monthly cycles. At ovulations, the levels increase rapidly. Then if fertilization does not occur, they drop back down. This sudden decline of progesterone and estrogen levels that trigger the menstrual cycle. If pregnancy occurs progesterone production increases shedding the lining of the uterus is prevented.