Analysis of the uterine artery pulsatility index on the day of endometrial transformation and pregnancy outcomes of patients undergoing frozen-thawed embryo transfer

Front Endocrinol (Lausanne). 2024 Apr 15:15:1278504. doi: 10.3389/fendo.2024.1278504. eCollection 2024.

Abstract

Objective: The objective was to analyze the impact of the uterine artery pulsatility index (PI) on pregnancy outcomes by measuring uterine artery blood flow on the day of endometrial transformation in patients undergoing frozen-thawed embryo transfer (FET).

Methods: This was a case-control study. In total, 2,036 patients who underwent FET at the Third Affiliated Hospital of Zhengzhou University from October 2019 to September 2020 were included. The patients were divided into a clinical pregnancy group and a nonclinical pregnancy group according to pregnancy outcome. A multivariate logistic regression model was used to analyze the factors affecting the clinical pregnancy rate. The receiver operating characteristic (ROC) curve was used to determine the optimal mean PI cutoff value of 1.75. After 1:1 propensity score matching (PSM), 562 patients were included. For statistical description and analysis, the patients were divided into two groups: a group with a mean PI > 1.75 and a group with a mean PI ≤ 1.75.

Results: The clinical pregnancy group included 1,218 cycles, and the nonclinical pregnancy group included 818 cycles. There were significant differences in female age (P<0.01), infertility type (P=0.04), baseline follicle-stimulating hormone level (P=0.04), anti-Müllerian hormone (AMH) level (P<0.01), antral follicle count (P<0.01), number of transferred embryos (P=0.045) and type of transferred embryo (P<0.01). There was no significant difference in the mean bilateral PI (1.98 ± 0.34 vs. 1.95 ± 0.35, P=0.10). The multivariate analysis results showed that maternal age (AOR=0.95, 95% CI=0.93-0.98, P<0.01), AMH level (AOR=1.00, 95% CI=1.00-1.01, P=0.045), number of transferred embryos (AOR=1.98, 95% CI=1.47-2.70, P<0.01), and type of transferred embryo (AOR=3.10, 95% CI=2.27-4.23, P<0.01) were independent factors influencing the clinical pregnancy rate. The mean PI (AOR=0.85, 95% CI=0.70-1.05; P=0.13) was not an independent factor influencing the clinical pregnancy rate. Participants were divided into two groups according to the mean PI cutoff value of 1.75, and there was no significant difference between the two groups (P > 0.05).

Conclusion: In this study, we found that the uterine artery PI on the day of endometrial transformation in patients undergoing FET is not a good predictor of pregnancy outcomes.

Keywords: endometrial transformation day; frozen-thawed embryo transfer; pregnancy outcome; pulsation index; uterine artery.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Case-Control Studies
  • Cryopreservation*
  • Embryo Transfer* / methods
  • Endometrium* / blood supply
  • Endometrium* / diagnostic imaging
  • Female
  • Fertilization in Vitro / methods
  • Humans
  • Pregnancy
  • Pregnancy Outcome*
  • Pregnancy Rate*
  • Pulsatile Flow* / physiology
  • Retrospective Studies
  • Uterine Artery* / diagnostic imaging
  • Uterine Artery* / physiology

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was supported by the 2020 Henan Province Medical Science and Technology Research and Joint Construction Project (LHGJ20200470); the National Key R&D Program “Fertility Health and Health Security for Women and Children”: Clinical Cohort and Intervention Study on Genetic Problems in Assisted Reproduction Offspring (2021YFC2700602); and the National Natural Science Foundation of China (81904291).