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. 2025 Apr 3;25(1):391.
doi: 10.1186/s12884-025-07508-0.

Prediction of clinical pregnancy after frozen embryo transfer based on ultrasound radiomics: an analysis based on the optimal periendometrial zone

Fangfang Xu #  1 , Ying Zhang #  2 , Qianqing Ma #  3 , Lili Hu  1 , Yu Li  1 , Chuanfen Gao  1 , Peipei Guo  4 , Xianyue Yang  1 , Yi Zhou  1 , Jie Zhang  5 , Heng Wang  6 , Chaoxue Zhang  7
Affiliations

Prediction of clinical pregnancy after frozen embryo transfer based on ultrasound radiomics: an analysis based on the optimal periendometrial zone

Fangfang Xu et al. BMC Pregnancy Childbirth. .

Abstract

Background: To investigate the optimal periendometrial zone (PEZ) in ultrasound (US) images and assess the performance of ultrasound radiomics in predicting the outcome of frozen embryo transfer (FET).

Methods: This prospective study had 422 female participants (training set: n = 358, external validation set: n = 64). We delineated the region of interest (ROI) of the endometrium (EN) from ultrasound images of the median sagittal surface of the uteri of patients. We determined the ROIs of PEZ on US images by automatically expanding 2.0, 4.0, 6.0, and 8.0 mm radii surrounding the EN. We determined the radiomics characteristics based on the ROIs of the endometrium and PEZ, then compared the different sizes of PEZ to determine the optimal PEZ. We constructed models of the EN and optimal PEZ using six machine learning algorithms. We developed a combined model using the radiomics characteristics of EN and the optimal PEZ. We evaluated the performance of the three models using the area under the curve (AUC).

Results: The optimal PEZ was 4.0 mm with a maximum AUC of 0.715 (95% confidence interval (CI): 0.581 - 0.833) in the external validation set. The combined radiomics model (endometrium and PEZ4.0 mm) yielded the best predictive performance with AUC = 0.853 (95% CI: 0.811 - 0.890) for the training set and AUC = 0.809 (95% CI: 0.696 - 0.909) for the external validation set.

Conclusions: PEZ4.0 mm could be the optimal area for predicting clinical pregnancy after FET. An US-based radiomics model that combines EN and PEZ4.0 mm demonstrated strong potential in helping clinicians predict FET outcomes more accurately, thereby supporting informed decision-making before treatment.

Keywords: Endometrial Receptivity; Frozen-embryo transfer; Radiomics; Ultrasound.

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Conflict of interest statement

Declarations. Ethics approval and consent to participate: This study was conducted in accordance with the principles of the Declaration of Helsinki and approved by the Ethics Review Committee of the First Affiliated Hospital of Anhui Medical University (Approval No. PJ2023-07–11). All participants signed the relevant forms to provide informed consent. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
The flow chart of this study. ART assisted reproductive technology; EMT endometrial thickness; FET frozen embryo transfer; TVS transvaginal ultrasound
Fig. 2
Fig. 2
The radiomics flow chart of the study. PEZ periendometrial zone; ROI Regions-of- interest; EN endometrium; LR logistic regression; SVM support vector machine; RF random forest classifier; DT decision tree classifier; KNN k-nearest neighbor classifier; BPNN Back Propagation Neural Network
Fig. 3
Fig. 3
ROC and DCA of three models in the training and external validation set. a ROC of three models in the training set; b ROC of three models in the external validation set; (c) DCA of three models in the training set. d DCA of three models in the external validation set. DCA decision curve analysis; ROC receiver operating characteristic; EN endometrium; PEZ periendometrial zone
Fig. 4
Fig. 4
SHAP summary plot shows the importance of all features. Each feature on the y axis and the SHAP value on the x axis. The SHAP value means the contribution of each feature to the model prediction, with the foremost feature displaying at the top of the image
See this image and copyright information in PMC

References

    1. Glujovsky D, Lattes K, Miguens M, Pesce R, Ciapponi A. Personalized embryo transfer guided by endometrial receptivity analysis: a systematic review with meta-analysis. Hum Reprod. 2023;38(7):1305–17. 10.1093/humrep/dead098. - PubMed
    1. Ouyang Y, Peng Y, Mao Y, Zheng M, Gong F, Li Y, Li X. An endometrial receptivity scoring system evaluated by ultrasonography in patients undergoing frozen–thawed embryo transfer: a prospective cohort study. Front Med. 2024;11. 10.3389/fmed.2024.1354363. - PMC - PubMed
    1. Gallos ID, Khairy M, Chu J, Rajkhowa M, Tobias A, Campbell A, Dowell K, Fishel S, Coomarasamy A. Optimal endometrial thickness to maximize live births and minimize pregnancy losses: Analysis of 25,767 fresh embryo transfers. Reprod Biomed Online. 2018;37(5):542–8. 10.1016/j.rbmo.2018.08.025. - PubMed
    1. Maged AM, Kamel AM, Abu-Hamila F, Elkomy RO, Ohida OA, Hassan SM, Fahmy RM, Ramadan W. The measurement of endometrial volume and sub-endometrial vascularity to replace the traditional endometrial thickness as predictors of in-vitro fertilization success. Gynecol Endocrinol. 2019;35(11):949–54. 10.1080/09513590.2019.1604660. - PubMed
    1. Kuijsters NPM, Methorst WG, Kortenhorst MSQ, Rabotti C, Mischi M, Schoot BC. Uterine peristalsis and fertility: current knowledge and future perspectives: a review and meta-analysis. Reprod Biomed Online. 2017;35(1):50–71. 10.1016/j.rbmo.2017.03.019. - PubMed

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