Perifollicular Vascularity and Its Relationship with Oocyte Maturity and IVF Outcome

Abstract

New markers of embryo ability to implant are pursued continuously. Understanding whether an oocyte is really "mature," that is, ready to be fertilized, would be of great help in choosing an embryo that will implant. It is usual to pay attention to the phase of meiosis, considering the extrusion of the polar body (metaphase II) to be the only sign of the maturity of the oocytes. Nevertheless, understanding more about how the cytoplasm contributes to an oocyte's competency also shows promise as a method of predicting which embryos will implant. Some studies about perifollicular vascularity have demonstrated that embryos originating from oocytes developed in well-vascularized follicles have a higher implantation rate than those originating from oocytes developed in follicles with poor vascularization. Here, we report our results from a preliminary study in which embryos were transferred according to the degree of vascularization of the follicle. Women who received embryos originating from oocytes developed in well-vascularized follicles had a statistically higher pregnancy rate than women who received embryos deriving from oocytes grown in more poorly vascularized follicles (34% vs. 13.7%).

Power Doppler ultrasound assessment of follicular vascularity in the early follicular phase and its relationship with outcome of in vitro fertilization

“…The significantly higher proportion of large follicles with high grade PFBF in the late follicular phase and significantly higher clinical pregnancy rate in "good beginners" in our study indirectly shows the association between a high grade PFBF in the late follicular phase with a high clinical pregnancy rate, confirming the findings of the other PDU studies (5)(6)(7). This study also demonstrated that the mean number of oocytes retrieved was significantly higher in "good beginners" compared to "poor beginners," supporting the findings by Bhal et al (6).…”

“…The information on proportion of grade 3 and 4 was not available in the PDU study by Borini et al (7). The most likely explanation for this difference in the proportion of grade 3 and 4 follicles between the present study and the other studies is that the ovarian PFBF in the above cited studies(5-7) was assessed on the day of egg pick up (approximately 32-34 h following hCG administration) compared to all PFBF assessments being performed prior to the hCG trigger in our study.…”

“…Similarly, it had been demonstrated that ovarian perifollicular vascularity assessed by power Doppler ultrasound (PDU) on the day of egg pick up is an in vivo ovarian marker of implantation potential (5)(6)(7). These authors demonstrated that the clinical pregnancy rate in IVF is significantly higher when the embryos transferred were derived from highly vascularized follicles.…”

“…Power Doppler ultrasound assessment of ovarian perifollicular vascularity on the day of egg pick up helps to select oocytes which develop into the embryos with better potential for implantation (5)(6)(7). While it is useful to know which follicles at egg collection contain good quality oocytes, it would also be useful to identify early characteristics of cycles that produce good quality oocytes.…”

Follicle and corpus luteum size and vascularity as predictors of fertility at the time of artificial insemination and embryo transfer in beef cattle

“…Therefore, since it is a non invasive technique and with reliable application, it is a useful tool to target new reproductive diagnoses. The evaluation of perifollicular vascularity was done in cows (Siddiqui et al 2008), women (Coulam et al 1999, Bhal et al 2001, Borini et al 2001, and mares (Silva et al 2006), and in all of these species was detected greater vascularity in the preovulatory follicle wall in individuals that became pregnant after mating.…”