Analysis of the guidance value of 3D ultrasound in evaluating endometrial receptivity for frozen-thawed embryo transfer in patients with repeated implantation failure.

Original Article Page 1 of 9 Analysis of the guidance value of 3D ultrasound in evaluating endometrial receptivity for frozen-thawed embryo transfer in patients with repeated implantation failure Ruiqing Tong, Ying Zhou, Qi He, Yanyan Zhuang, Weiqin Zhou, Fei Xia Reproductive Medicine Center of the First Affiliated Hospital of Soochow University, Suzhou 215006, China Contributions: (I) Conception and design: R Tong; (II) Administrative support: F Xia; (III) Provision of study materials or patients: R Tong, Y Zhou; (IV) Collection and assembly of data: Q He, W Zhou; (V) Data analysis and interpretation: R Tong, Y Zhuang; (VI) Manuscript writing: All authors; (VII) Final approval of manuscript: All authors. Correspondence to: Fei Xia. Reproductive Medicine Center of the First Affiliated Hospital of Soochow University, Suzhou 215006, China. Email: . Background: Repeated implantation failure (RIF) is currently believed by some scholars to be mainly related to the poor endometrial receptivity. Three-dimensional (3D) ultrasound, as a noninvasive examination, has attracted the most attention. This paper further discusses whether 3D ultrasound of the endometrial receptivity index has guidance value in the evaluation of pregnancy outcomes in patients with RIF following frozen-thawed embryo transfer. Methods: A total of 79 patients with RIF were retrospectively analyzed. These 79 patients which were confirmed by the transvaginal ultrasonography detection comprised 36 cases of intrauterine pregnancy, which were included in the pregnancy group, and 43 cases with biochemical pregnancy (the HCG in blood or urine is only transient and can be detected by clinical biochemical methods. The pregnancy sac cannot be seen under ultrasound) or negative results of human chorionic gonadotropin (HCG) examination, which were included in the non-pregnancy group. The endometrial thickness, uterine volume, sub-endometrial blood flow type, pulsatility index (PI) and resistance index (RI) of the spiral artery; the RI and PI of the uterine artery; and the peak systolic velocity/end diastolic velocity (S/D) of the two groups were measured and analyzed. Results: (I) There were no significant differences in the age, infertility years, body mass index (BMI), anti-Müllerian hormone (AMH), endometrial thickness on the hCG injection day, estradiol (E2), and progesterone (P) between the pregnant and non-pregnant groups (P>0.05). (II) There were no significant differences in the endometrial thickness, uterine volume, and RI and PI of the uterine artery on the day before the implantation between the two groups (P>0.05). (III) There was statistical difference in the sum of the S/D of the two uterine arteries between the two groups (P<0.05) with a cutoff value of 14.47 (P<0.05). (IV) The RI and PI of the spiral artery in the non-pregnancy group were lower than those in the pregnancy group, and the difference was statistically significant (P<0.05). (V) The differences in the endometrial classification and subendometrial blood flow classification between the two groups were statistically significant (P<0.05). Conclusions: Ultrasonographic endometrial blood flow classification, spiral artery blood flow parameters, and uterine artery blood flow parameters can be effective indexes for evaluating endometrial receptivity, and they have a certain clinical significance in evaluating the pregnancy outcome of RIF patients after retransplantation. Keywords: 3D ultrasound; endometrial receptivity; repeated implantation failure (RIF); frozen-thawed embryo transfer © Annals of Translational Medicine. All rights reserved. Ann Transl Med 2020;8(15):944 | http://dx.doi.org/10.21037/atm-20-5463 Tong et al. Analysis of the guidance value of 3D ultrasound in evaluating endometrial receptivity Page 2 of 9 Submitted Jun 21, 2020. Accepted for publication Aug 04, 2020. doi: 10.21037/atm-20-5463 View this article at: http://dx.doi.org/10.21037/atm-20-5463 Introduction Methods Repeated implantation failure (RIF) refers to a failure to achieve clinical pregnancy after transfer of at least four good-quality embryos in a minimum of three fresh or frozen cycles in a woman under the age of 40 years (1,2). The causes for RIF are very complex and generally involve factors related to the embryo and endometrium. RIF is currently believed by some scholars to be mainly related to poor endometrial receptivity. Clinically, the common factors that affect endometrial receptivity are hydrosalpinx, endometriosis, adenomyosis, endometritis, hysteromyoma, and the change of endogenous hormone level caused by superovulation. Current methods of abortion treatment include anticoagulant therapy, immunosuppression, immunoregulation and gene screening, etc. At present, the main methods to evaluate endometrial receptivity include endometrial receptivity-related markers (such as pinocytosis), endometrial receptivity factors, and ultrasonography. Among these, three-dimensional (3D) ultrasound, as a non-invasive examination, has received more attention in evaluating endometrial receptivity by virtue of its ability to monitor endometrial thickness, endometrial peristalsis wave, endometrial typing, volume ultrasound, and endometrial and subendometrial blood flow parameters. It is generally believed that endometrial volume measurement is more accurate than endometrial thickness in evaluating endometrial receptivity and that it is a good index to predict endometrial receptivity. In this study, there was no significant difference. In order to further explore the value of 3D ultrasound in evaluating endometrial receptivity in patients with RIF following frozen-thawed embryo transfer, this study retrospectively analyzed the data of 79 patients with RIF who received frozen-thawed embryo transfer in our center from January 2018 to December 2019. We further explored whether 3D ultrasound of the endometrial receptivity index had guidance value in the evaluation of pregnancy outcome of the patients with RIF following frozen-thawed embryo transfer. We present the following article in accordance with the MDAR reporting checklist (available at http://dx.doi. org/10.21037/atm-20-5463). All procedures performed in this study involving human participants were in accordance with the Declaration of Helsinki (as revised in 2013). This study was approved by Medical ethics committee of the First Affiliated Hospital of Suzhou University (No. 137). Because of the retrospective nature of the research, the requirement for informed consent was waived. © Annals of Translational Medicine. All rights reserved. Research subjects A retrospective analysis was made of 79 patients with RIF who received frozen-thawed embryo transfer in the Reproductive Medicine Center of the First Affiliated Hospital of Soochow University from January 2018 to December 2019 and met the inclusion and exclusion criteria of this study. Among them, 36 cases of intrauterine pregnancy indicated by transvaginal u (...truncated)