Diagnostic value of serum human chorionic gonadotropin and uterine artery Doppler indices in missed abortion

Abstract

Objective: To evaluate the combined diagnostic value of serum human chorionic gonadotropin (HCG) levels and uterine artery Doppler indices - including pulsatility index (PI), resistance index (RI), peak systolic velocity (PSV), and end-diastolic velocity (EDV) - for identifying missed abortion.

Methods: This retrospective cohort study included 160 patients diagnosed with missed abortion and 200 women with normal pregnancies between January 2019 and December 2023. Serum HCG levels were measured using electrochemical immunoassay, and uterine artery Doppler indices were obtained by transvaginal ultrasound. Statistical analyses included independent t-tests, Pearson correlation, receiver operating characteristic (ROC) curve analysis, and Akaike information criterion (AIC)-based model selection to assess diagnostic performance.

Results: Compared to normal pregnancies, patients with missed abortion had significantly lower HCG levels and significantly higher PI, RI, and EDV values (all P < 0.001). Serum HCG levels were negatively correlated with PI (r = -0.33), RI (r = -0.24), PDV (r = -0.25), and EDV (r = -0.26). The combined diagnostic model incorporating HCG, PI, RI, PSV, and EDV demonstrated the highest diagnostic accuracy, with an area under the curve (AUC) of 0.941 (95% CI: 0.918-0.964), sensitivity of 86.25%, and specificity of 87.00%.

Conclusion: Combining serum HCG levels with uterine artery Doppler indices markedly enhanced the diagnostic accuracy for missed abortion compared to single biomarkers. This multimodal approach offers high sensitivity and specificity, and may be useful in clinical practice.

Keywords: Missed abortion; human chorionic gonadotropin (HCG); uterine artery Doppler.

Figure 1

Intergroup differences in uterine artery blood flow indices and serum HCG levels. A: Serum HCG levels (mIU/mL); B: Pulsatility Index (PI); C: Resistance Index (RI); D: Peak Diastolic Velocity (PDV); E: End-Diastolic Velocity (EDV); F: S/D Ratio. Note: HCG, Human Chorionic Gonadotropin; PI, Pulsatility Index; RI, Resistance Index; PDV, Peak Diastolic Velocity; EDV, End-Diastolic Velocity; NS, not statistically significant. P > 0.05, ***: P < 0.001.

Figure 2

Correlation analysis between uterine artery blood flow indicesand serum HCG levels. A: Serum HCG levels vs. PI; B: Serum HCG levels vs. RI; C: Serum HCG levels vs. PDV; D: Serum HCG levels vs. EDV; E: Serum HCG levels vs. S/D Ratio. Note: HCG, Human Chorionic Gonadotropin; PI, Pulsatility Index; RI, Resistance Index; PDV, Peak Diastolic Velocity; EDV, End-Diastolic Velocity; S/D, Systolic-Diastolic Ratio.

Figure 3

ROC curve analysis of diagnostic value of uterine artery blood flow indices and serum HCG levels for missed abortion. A: ROC curves showing AUC for individual models; B: Comparison of AUC among models. Note: PI, Pulsatility Index; RI, Resistance Index; PSV, Peak Diastolic Velocity; EDV, End-Diastolic Velocity; S/D, Systolic-Diastolic Ratio; AUC, Area Under the Curve.

Figure 4

Distribution of AIC values across diagnostic models. Note: AIC, Akaike Information Criterion; HCG, Human Chorionic Gonadotropin; PI, Pulsatility Index; RI, Resistance Index; PSV, Peak Diastolic Velocity; EDV, End-Diastolic Velocity.

Figure 5

ROC curve analysis and model comparison. A: ROC curves showing AUC for each model; B: Comparison of AUC among models. Note: ROC, Receiver Operating Characteristic Curve; AUC, Area Under the Curve; HCG, Human Chorionic Gonadotropin; PI, Pulsatility Index; RI, Resistance Index; PSV, Peak Diastolic Velocity; EDV, End-Diastolic Velocity.