Follicular vascularity--the predictive value of transvaginal power Doppler ultrasonography in an in-vitro fertilization programme: a preliminary study

Abstract

The aim of this prospective study was to investigate the ability of transvaginal power Doppler ultrasonography to assess the relationship between follicular vascularity and outcome in women undergoing in-vitro fertilization. Each of 38 subjects underwent a single transvaginal power Doppler ultrasound scan on the day of oocyte collection, where the vascularity of individual ovarian follicles was assessed, using a subjective system, and graded 1 to 4. In addition, conventional pulsatility indices (PI) of the uterine and intra-ovarian (stromal) arteries were calculated, which showed no significant differences between the pregnant and non-pregnant groups. Using power Doppler ultrasonography, a total of 188 follicles was studied. The follicular vascularity grade was found to be independent of follicular size and there was no significant difference in fertilization rates with different degrees of vascularity, although there was a trend towards higher fertilization rates with higher grade vascularity. There were 10 pregnancies, giving a pregnancy rate of 26.3% per embryo transfer. Pregnancies were confined to those women whose embryos were derived from follicles with grade 3 and 4 vascularity (pregnancy rates per embryo transfer of 12.5 and 61.5% respectively), with only those from grade 4 follicles resulting in livebirths. This preliminary study suggested that high grade follicular vascularity is associated with increased pregnancy rate and that there is a possible link between follicular vascularity and implantation potential.

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).…”

“…Ovarian PFBF was graded using the modified grading system (Grade 0: 0%, Grade 1: 1-25%, Grade 2: 26-50%, Grade 3: 51-75%, Grade 4: 76-100%) based on Chui et al (5). In other words, Grade 0 follicles do not have any detectable blood flow around the follicular circumference, Grade 1 follicles have blood flow visible in 1-25% of the follicular circumference; Grade 2 follicles have blood flow visible in 26-50% of the follicular circumference, Grade 3 follicles have blood flow visible in 51-75% of the follicular circumference, and Grade 4 follicles have blood flow visible in 76-100% of the follicular circumference.…”

“…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.…”

Power doppler ultrasound assessment of the relationship between age and ovarian perifollicular blood flow in women undergoing in vitro fertilization treatment

“…Ovarian perifollicular blood flow (PFBF) assessment during IVF using PDU has been demonstrated to be a good marker of oocyte competence, embryo viability, and subsequent implantation potential [10] with a number of studies showing a higher pregnancy rate if embryos resulting from the fertilization of eggs from better perfused follicles are transferred [11][12][13][14].…”