Luteal phase defect is disorder of low progesterone secretion (low level), or very short luteal phase (shorter than 11 days). Consequence of that is late endometrium maturation, almost 2 days. Such endometrum impedes and makes impossible ovum nidation. Today we have luteal phase defect in 14% of infertility women, and in 21% of women of unknown infertility reason. This has been frequently seen in women with spontaneous abortion and hyperprolaktinemia. Diagnostic methods of DLF are biopsy of endometrium and measuring of progesterone level. The aim of this study is the examine endometrium maturation disorders. The study includes 30 women that are hospitalized in Clinical of Gynecology Pristina. Unknown reason of infertility and normal hormonal status had been in 13 (43%), and hyperprolaktinemia in 7 (56,7%) of women. Histological verificated ovulation had been finding out in 60%of women. Late endometrium maturation, luteal phase defect, had been verificated in 23,3% of women, from there in 29,4% of hyperprolaktinemic women and in 5,4% of women of unknown infertility reason. There was evidence of late endometrium maturation of 2 days (85,7%). and of 4 days th (5,4%). Progesterone level in DFLthe 20th day was 30 nmol/l, the 24 day of menstrual cycle was 28,8 nmol/l. Progesterone level in women with histological proved regular endometrium maturation was higher and it was 45, nmol/l. The lowest progesterone level that can be find in good functioning of luteal body was 31,8 nmol/l.Citohormonal findings in DFL was showing progesterone domination. Take a look at infertility and ovarian function must not be concern only on ovulation, it must take care of endometrium maturation.