Effect of pituitary downregulation on antral follicle count, ovarian volume and stromal blood flow measured by three-dimensional ultrasound with power Doppler prior to ovarian stimulation

BAckground: Despite the extensive use of gonadotrophin releasing hormone agonists (GnRH ag) for pituitary downregulation, the literature regarding their effect on ultrasound parameters for predicting ovarian responses are few and conflicting. The aim of this prospective study was to compare antral follicle count (AFC), ovarian volume and ovarian stromal blood flow measured by three-dimensional (3D) power Doppler ultrasound before and after pituitary downregulation. Methods: All patients received a long protocol of intranasal Buserelin from the mid-luteal phase of the cycle. In the early follicular phase of the preceding cycle before downregulation and on the second day of the treatment cycle after downregulation, patients underwent a blood test for serum FSH, LH and estradiol and a transvaginal scanning with 3D power Doppler to determine AFC, ovarian volume and ovarian 3D power Doppler flow indices. Results: Out of 104 women scanned, 85 women were analysed. Polycystic ovaries were encountered in 14 (16.5%) women. No significant differences in any of the ultrasound parameters were demonstrated before and after downregulation, in patients with normal ovaries or in those with polycystic ovaries. Conclusion: AFC, ovarian volume and ovarian 3D power Doppler flow indices did not significantly change after a short-term treatment of GnRH agonist for pituitary downregulation.