Ovulatory disturbances in patients with luteal insufficiency.

In order to study ovulatory disturbances in patients with luteal insufficiency we evaluated 210 cycles of 170 women from infertile couples by ultrasonographic follicle measurements and hormonal determinations. Only cycles with evidence of luteinization were included into the study. Mid-luteal progesterone (P) levels were determined in relation to the ultrasonographic ovulation time or, where the follicle failed to rupture, in relation to the LH peak. In spontaneous cycles with a mid-luteal P level below 32 nmol/l (10 ng/ml) a luteinized unruptured follicle (LUF) was found in 71.1% of cycles, whereas in spontaneous cycles with a mid-luteal P level above 32 nmol/l only 7.9% cycles exhibited a failure of the follicle to rupture. The same phenomenon was encountered in cycles in which agents had been given to induce ovulation. The incidence of LUF cycles in an average infertility population could be calculated to be as high as 50% if the mid-luteal P level is below 32 nmol/l and as low as 4% if the mid-luteal P level is above 32 nmol/l. The geometric mean mid-luteal P level in spontaneous LUF cycles was 32.5 nmol/l, compared to 55.2 nmol/l in spontaneous ovulatory cycles (P less than 0.001). We conclude that in patients with luteal insufficiency a high incidence is found of a failure of the follicle to rupture. The entrapment of the oocyte in the unruptured follicle constitutes an important cause of infertility in these patients.