Assessing Uterine Receptivity in 2001

Abstract

The understanding and control of embryo implantation represents the major challenge for assisted reproductive technologies. Along with developments in basic research and efforts to optimize embryo quality, the improvement of noninvasive and reliable methods to assess uterine receptivity constitutes an important step toward meeting such a challenge. Today, ultrasound-based approaches to evaluate endometrial echogenicity and uterine perfusion and contractility are available for practical use. Increasing evidence indicates that echogenic patterns of the endometrium reflect histologic processes that are involved in the establishment of receptivity. This constitutes a possible explanation for the reported association between premature hyperechogenic patterns of the endometrium and poor implantation rates. Nevertheless, additional studies aiming at correlating further morpho-biochemical events in the endometrium with its echogenicity patterns are needed. Further, developments in vascular assessment by Doppler, Doppler-related, and vascular detection technologies will also be instrumental in monitoring and improving vascular changes that lead to uterine receptivity. Finally, data supporting the hypothesis that uterine contractility, as visualized by ultrasound, influences in vitro fertilization-embryo transfer (IVF-ET) pregnancy rates encourage further investigation on both the regulation and control of uterine contractions. This article discusses some of the advantages and limitations of ultrasonographic assessments of uterine receptivity in the perspective of the new millennium.

Thin Endometrium and Cleavage Embryo Transfer Are Associated With Ectopic Pregnancy After in Vitro Fertilization‑embryo Transfer Cycles: a Matched Case–control Study Using Propensity Score Matching

“…A variety of studies have suggested that ultrasound can be used as a noninvasive and simple method to assess the endometrial receptivity [52] . Several sonographic parameters have been evaluated, including EMT, endometrial pattern, endometrial volume and endometrial and subendometrial blood ow [53][54][55][56][57] .…”

The Challenge of Improving IVF Results in Normogonadotrophic (Unexpected) Young Poor Ovarian Responders: The Predictive Value of a Flexible Treatment Protocol Based on the “Biophysical Profile of the Uterus”

“…Up to 85% of the embryos replaced into the uterine cavity fail to implant [39]. This, in addition to the quality of the embryos, very much depends on the overall uterine receptivity and the timing of the embryo transfer (ET) [40] [41]. Since the introduction of Assisted Reproduction there has been a significant progress in improving ovarian stimulation, oocyte retrieval, IVF and embryo transfer.…”

Changes in cell proliferation, but not in vascularisation are characteristic for human endometrium in different reproductive failures - a pilot study

“…Although the importance of angiogenesis for implantation, and normal uterine and placental function is well recognized [16,42,43], the role of inadequate vascularization or blood flow in implantation failure has not been investigated in detail. Inconsistent results of impact of uterine blood flow in implantation failure measured by ultrasound technologies were obtained [16,17]. For example, using ultrasound techniques [44], reduced endometrial and subendometrial 'perfusion' has been demonstrated which suggests a reduced vascularity in women with unexplained subferitility, irrespective of E2 and progesterone levels.…”