Mapping the way to successful euploid frozen embryo transfer: a prospective pilot study of uterine shear wave elastography (swe)

To determine whether objective and quantitative assessment of uterine tissue stiffness via ultrasound SWE is predictive of outcome after single euploid frozen embryo transfer (FET). This was a prospective pilot study of 153 patients with no known uterine pathology undergoing single euploid FET at a university-affiliated center between June - December 2022. All FET endometrial preparation protocols were allowed. On the day prior to FET, SWE assessment of 15 regions of interest (ROI) measuring 6mm in diameter were performed by a SWE trained sonographer via the Samsung RS85 Prestige Ultrasound. ROI’s were selected to evaluate the entire uterus and included the cervix, myometrium, fundus, endometrium, and the anterior myometrial/endometrial interface. The SWE data points generated from ultrasound were then collected in a standardized fashion by a single investigator blinded to patient outcome. The elasticity parameters (in kilopascals, kPA’s, and meters per second, m/s) were obtained for each ROI and assessed for relationship to sustained implantation (SI), defined as discharge from fertility care at 9 weeks gestation. All elasticity parameters were analyzed, including the mean, standard deviation (SD), minimum and maximum values in kPA’s and m/s for all ROI. SWE data were analyzed using Student’s T-test. Multivariate stepwise backwards logistic regression was used to develop a ROC model for predicting SI. There were 11 SWE measurements that showed a significant relationship to SI with p