Huang Wenjie, Tang Juan, Wei Liuyan, Nong Liuying, Tang Ni, Wei Xiaohua, Zhang Fan, Yao Chunling, Li Jingjing, Fan Li
Department of Reproductive Medicine, Guangzhou Women and Children's Medical center Liuzhou Hospital, Liuzhou, Guangxi, China.
Department of Reproductive Medicine, Liuzhou maternity and Child Healthcare Hospital, Liuzhou, Guangxi, China.
Front Cell Dev Biol. 2025 Mar 7;13:1530953. doi: 10.3389/fcell.2025.1530953. eCollection 2025.
Endometrial thickness (EMT) is a crucial indicator of endometrial receptivity in assisted reproductive technology (ART). However, its relationship with pregnancy outcomes remains unclear, especially across different cycle types such as fresh fertilization-embryo transfer (IVF-ET), frozen-thawed embryo transfer (FET), and preimplantation genetic testing for aneuploidy embryo transfer (PGT-ET). The clinical significance of EMT and its optimal range for improving ART outcomes remain subjects of debate.
This retrospective cohort study analyzed data from 80,585 ART cycles conducted between July 2008 and December 2022 at a private reproductive center, including 25,683 fresh IVF-ET, 33,112 FET, and 1,071 PGT-ET cycles. EMT was measured via ultrasound on the day of HCG administration and grouped into ranges for comparison. Primary outcomes included live birth rates (LBR) and clinical pregnancy rates (CPR) across EMT ranges. Statistical analyses, including chi-square tests, receiver operating characteristic (ROC) analysis, and adjusted risk ratio (aRR) calculations, were performed to evaluate the association between EMT and pregnancy outcomes.
The relationship between EMT and LBR was non-linear, with no single cutoff value. LBR varied significantly across EMT ranges, peaking at approximately 12 mm in fresh IVF-ET cycles and around 10 mm in FET and PGT-ET cycles. Higher EMT was generally associated with improved LBR and CPR, but predictive power was limited (AUC: 0.56-0.60). Compared to an EMT of 10-11.9 mm, fresh IVF-ET cycles with EMT <10 mm had significantly lower LBR (aRR: 0.60-0.86), while those with EMT ≥12 mm had higher LBR (aRR: 1.12-1.17). Similar trends were observed in FET and PGT-ET cycles, although sensitivity to EMT variations was lower, particularly in PGT-ET cycles. Miscarriage rates (MR) showed no significant differences across EMT groups.
This study demonstrates that EMT has a non-linear association with LBR and CPR across fresh IVF-ET, FET, and PGT-ET cycles, with no single cutoff value. While higher EMT generally correlates with improved outcomes, its overall predictive value for LBR is limited. The findings underscore the need for individualized evaluation of EMT based on cycle type to optimize reproductive outcomes in ART.
子宫内膜厚度（EMT）是辅助生殖技术（ART）中子宫内膜容受性的关键指标。然而，其与妊娠结局的关系仍不明确，尤其是在不同的周期类型中，如新鲜受精胚胎移植（IVF-ET）、冻融胚胎移植（FET）和非整倍体胚胎移植的植入前基因检测（PGT-ET）。EMT的临床意义及其改善ART结局的最佳范围仍是争论的话题。
这项回顾性队列研究分析了2008年7月至2022年12月在一家私立生殖中心进行的80585个ART周期的数据，包括25683个新鲜IVF-ET周期、33112个FET周期和1071个PGT-ET周期。在注射人绒毛膜促性腺激素（HCG）当天通过超声测量EMT，并分组进行比较。主要结局包括不同EMT范围内的活产率（LBR）和临床妊娠率（CPR）。进行了包括卡方检验、受试者工作特征（ROC）分析和调整风险比（aRR）计算在内的统计分析，以评估EMT与妊娠结局之间的关联。
EMT与LBR之间的关系是非线性的，没有单一的临界值。LBR在不同的EMT范围内有显著差异，在新鲜IVF-ET周期中约12mm时达到峰值，在FET和PGT-ET周期中约10mm时达到峰值。较高的EMT通常与改善的LBR和CPR相关，但预测能力有限（曲线下面积：0.56 - 0.60）。与EMT为10 - 11.9mm相比,EMT<10mm的新鲜IVF-ET周期的LBR显著较低（aRR：0.60 - 0.86），而EMT≥12mm的周期LBR较高（aRR：1.12 - 1.17）。在FET和PGT-ET周期中观察到类似趋势，尽管对EMT变化的敏感性较低，特别是在PGT-ET周期中。流产率（MR）在不同EMT组之间没有显著差异。
本研究表明，在新鲜IVF-ET、FET和PGT-ET周期中,EMT与LBR和CPR之间存在非线性关联，没有单一的临界值。虽然较高的EMT通常与改善的结局相关，但其对LBR的总体预测价值有限。研究结果强调需要根据周期类型对EMT进行个体化评估，以优化ART中的生殖结局。
