In females showing fibrous-cystic mastopathy and fibroadenomatosis of mammary glands a specific form of progesterone insufficiency- relative one, was revealed, a high persistantly maintained level of urine pregnandiol and blood progesterone in a luteal phase (indicating a high hormonal activity of the corpus luteum) being observed. But luteal transformations were insignificant both in endometrium and vaginal epithelium, a moderate hypoestrogenemia being noted in the first phase and increased estrogen excretion- in the second phase of the cycle.