Objective: The growth of the follicles induced by gonadotropins during IVF treatment is accompanied by physiologic angiogenesis, which is essential for the maturation of the oocytes. We describe the IVF-induced changes in the vascularization and compare normal with polycystic ovaries (PCOs).
Design: Prospective study.
Setting: Assisted reproductive unit at a university hospital.
Patient(s): Sixty women who underwent IVF cycles.
Intervention(s): The ovarian vascularization was measured after pituitary down-regulation, FSH stimulation, and hCG-injection using three-dimensional power Doppler ultrasonography.
Main outcome measure(s): The total ovarian vascularization was divided by the number of follicles.
Result(s): After pituitary suppression, the ovarian vascularization/follicle was lower in polycystic ovary (PCO) patients. During ovarian stimulation, follicles in PCOs required a lesser amount of FSH to acquire the same level of vascularization than the follicles in normal ovaries. In addition, hCG induced an increase in the follicular vascularization in both normal and PCOs. The follicle count correlated with the total vascularized volume in the ovaries throughout the IVF cycle.
Conclusion(s): Follicles in PCOs seem to be less vascularized than the follicles in normal ovaries after GnRH treatment but not after gonadotropin stimulation. It is possible that restricted blood supply to the follicles in PCO might be associated with the follicular arrest that is observed. We could confirm that follicles in PCO are more sensitive to gonadotropin stimulation than follicles in normal ovaries.