Luteinized unruptured follicle syndrome in mild endometriosis. Assessment with biochemical parameters

Failure to extrude an ovum, with subsequent luteinization of the unruptured follicle (LUF), has been proposed as a cause of infertility in women with mild endometriosis. To assess the incidence of this process we performed laparoscopies in the early luteal phase on 16 women with mild endometriosis and 8 control subjects. Peritoneal fluid was aspirated and a plasma sample obtained concurrently. Estradiol (E2) and progesterone (P) concentrations were determined. A review of the literature suggested that the following hormonal criteria correlated with follicular rupture: fluid E2 greater than or equal to 500 pg/ml, E2 fluid/plasma ratio greater than or equal to 3.1, fluid P greater than or equal to 3,000 ng/dl and P fluid/plasma ratio greater than or equal to 5:1. All control subjects met at least one E2 and one P criterion: 75% met all. In contrast, less than one-third with mild endometriosis met all, and three (19%) met none. Five met only E2 criteria. These findings suggest that LUF occurs occasionally in association with mild endometriosis. Additionally, ovarian steroidogenesis, particularly P secretion, was impaired frequently in the absence of LUF in women with endometriosis.