Ovarian markers of implantation potential in assisted reproduction

Abstract

In-vitro fertilization provides evidence for the heterogeneity of human embryos; data from the UK indicating that approximately 90% of embryos selected for transfer fail to implant. The need to identify factors that promote implantation or markers of implantation is self-evident. There is an increasing awareness that the heterogeneity of follicles may have a significant impact on oocyte competence and embryo viability and that factors which contribute to the heterogeneity of follicles may provide markers of implantation in assisted conception. The markers of implantation described include the expression of 11 beta-hydroxysteroid dehydrogenase by granulosa cells in vitro; adhesion and proliferation of cumulus cells in vitro; steroidogenic activity of cumulus in vitro and perifollicular vascularity and vascular endothelial growth factors bound to granulosa and cumulus cells. These factors may provide clinically useful markers of implantation potential.

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

“…Antral follicles (seen on ultrasound), unlike the preantral and primordial follicles, do not derive their blood flow directly from ovarian stromal vessels but develop, through the process of neovascularization, a vascular sheath consisting of arterioles, venules and capillaries in the surrounding theca layer [7,8]. Although the precise regulation of this cyclic angiogenesis and consequent neovascularization in the human ovary remains unclear, a number of angiogenic factors and inhibitors are likely to be involved including vascular endothelial growth factor (VEGF) [8,10,24]. In addition, a number of IVF studies have shown that each mature follicle has unique blood flow characteristics and perifollicular capillary bed development [4,11,26,27] supporting the concept that not all follicles are 'created equal' in terms of vasculature [25].…”

“…The sensitivity for the detection of blood flow was set at 0.09 cm/s for all the cases. During power Doppler ultrasound colour gain for all the cases was set at the level A3 [10], where A stands for amplitude and A3 denotes highest amount of persistence, 10 shows the level of colour gain when the noise (over-gaining) just disappears. All scans were performed by a single operator (SMS) at the same time each morning (between 7 am and 9.30 am), thus controlling the effects of circadian variation on blood flow [20].…”

“…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].…”

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

“…Data from the United Kingdom show that nearly 90% of embryos selected for transfer fail to implant (2). Poor oocyte/embryo quality and the poor endometrial receptivity are suggested to be the major causes of IVF treatment failure.…”

The Means of Progress in Improving the Results of in vitro Fertilization Based on the Identification and Correction of the Pathology of Hemostasis

“…Ovarian reserve is one of the factors that determine the efficacy of IVF (Gregory, 1998;Navot et al, 1987;Scheffer et al, 2003). Assessing the ovarian reserve, specialists draw conclusions based on the prospects of ovarian stimulation in a particular patient.…”