**5.3 Ovarian stromal vascularity**

The observation of the ovarian stromal Doppler flow during ovarian stimulation has been studied in IVF cycles. Poor ovarian stromal vascularization impairs the access of gonadotropins to the ovarian follicles. Power Doppler US in combination with 3D VOCAL is an appropriate approach for correlating the ovarian vascular network with the ovarian response to ART. The gradual increase in the Doppler flow noted during stimulation may provide additional information to AFC (**Figure 5**) [27–36].
