LEVELS OF INSULIN AND CHOLESTEROL IN HUMAN FOLLICULAR-FLUID

Objective-The intent of this study was to ascertain if there was a cor relation between insulin and cholesterol levels in follicular fluid an d oocyte fertilizability and developmental potential. Materials and Me thods-The levels of immunoreactive cholesterol, total cholesterol, hig h-density lipoprotein-cholesterol, very-low-density lipoprotein-choles terol, and low-density lipoprotein-cholesterol were determined in foll icular fluid samples obtained during transabdominal-transvesicular asp iration of follicles under ultrasound guidance, from patients treated with clomiphene citrate and human menopausal gonadotropin for in vitro fertilization. Insulin was measured by radioimmunoassay and cholester ol by an enzymatic method. Results-Follicles containing oocytes with b etter fertilizability and greater developmental potential possessed lo wer concentrations of immunoreactive insulin and high-density lipoprot ein-cholesterol, and higher concentrations of low-density lipoprotein- and very-low-density lipoprotein-cholesterol. Conclusion-These change s in the level of cholesterol carried by the various lipoproteins in t he follicular fluid strongly suggest that oocyte maturation is influen ced by insulin-dependent steroidogenesis.