Assessment of endometrial receptivity during implantation window in women with unexplained infertility

Abstract

This study aimed to assess the endometrial receptivity during implantation window in women with unexplained infertility. A prospective study recruited 168 women with unexplained infertility and 169 fertile women. Ultrasonic parameters and biomarkers in the uterine fluid were detected. The endometrial vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were significantly higher in fertile women as compared with unexplained infertile women, and the integrin αvβ3, vascular endothelial growth factor (VEGF), tumor necrosis factor alpha (TNF-α), and leukemia inhibitory factor (LIF) levels in uterine fluid were significantly higher in fertile women. The biochemical pregnancy rate, clinical pregnancy rate, and ongoing pregnancy rate in fertile women were 20.12%, 18.34%, and 17.75%, respectively, which were significantly higher compared with unexplained infertile women (7.14%, 5.36%, and 4.17%, respectively). Endometrial thickness (ET), endometrial volume (EV), VI, FI, and VFI measured by ultrasound, and the integrin αvβ3, VEGF, TNF-α, and LIF levels in uterine fluid were all significantly higher in pregnant women as compared with nonpregnant women. The best parameters of ultrasonic indicators for predicting endometrial receptivity in women with unexplained infertility were FI(AUC = 0.894, sensitivity 93.8%, and specificity 83.1%). Integrin αvβ3 had the best predictive value for endometrial receptivity among biomarkers in the uterine fluid (AUC = 0.921, sensitivity 96.7%, and specificity 89.5%). Women with unexplained infertility present declined endometrial receptivity. Endometrial ultrasonic parameters detected by three-dimensional power Doppler and biomarkers in the uterine fluid may be effective indicators to predict endometrial receptivity.

Chinese abstract

本研究旨在评估不明原因不孕女性种植窗期的子宫内膜容受性。该前瞻性研究纳入了168名不明原因不孕女性和169名有生育能力的女性。检测宫腔液的超声指标和生物标志物。生育女性子宫内膜血管化指数(VI)、血流化指数(FI)和血管化血流指数(VFI)显著高于不明原因不孕女性。育龄女性宫腔液中整合素αvβ3、血管内皮生长因子(VEGF)、肿瘤坏死因子α(TNF-α)和白血病抑制因子(LIF)水平显著升高。生育女性的生化妊娠率、临床妊娠率和持续妊娠率分别为20.12%、18.34%和17.75%, 显著高于不明原因不孕的女性(分别为7.14%、5.36%和4.17%)。超声测量妊娠女性其子宫内膜厚度(ET)、子宫内膜容积(EV)、VI、FI、VFI及宫腔液中整合素αvβ3、VEGF、TNF-α、LIF水平均显著高于非妊娠女性。超声预测不明原因不孕女性子宫内膜容受性的最佳指标为FI(AUC值为0.894, 灵敏度为93.8%, 特异度为83.1%)。在宫腔液的生物标志物中, 整合素αvβ3对子宫内膜容受性的预测价值最好(AUC＝0.921, 敏感度96.7%, 特异度89.5%)。不明原因不孕的女性子宫内膜容受性下降。三维能量多普勒测量的子宫内膜超声指标和宫腔液生物标志物可能是预测子宫内膜容受性的有效指标。

Keywords:

• Unexplained infertility
• implantation window
• endometrial receptivity
• ultrasonic parameters
• biomarkers

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by the basic research program of Natural Science of Shaanxi Province, China [grant number 2019JM-569].