早期妊娠喪失における薬物療法の陰性予測因子としての処置後残存厚

To determine the rate of pharmacological treatment failure in early pregnancy loss, assess post-treatment residua thickness as a predictor of retained products of conception (RPOC), identify a clinically relevant cutoff, and evaluate additional clinical and sonographic predictors.

This retrospective cohort study was conducted at a tertiary medical center and included patients treated with mifepristone-misoprostol for first-trimester pregnancy loss between January 2019 and January 2022. Treatment success was assessed via transvaginal ultrasound, with residua thickness measured 14 days post-treatment. The primary outcome was failure, defined as histologically confirmed RPOC following hysteroscopy. Secondary analyses evaluated clinical and sonographic predictors, focusing on post-treatment residual thickness. Statistical analysis included receiver operating characteristic (ROC) curve assessment and multivariable logistic regression.

Of the 717 patients included, 537 (74.9%) achieved successful medical management without further intervention, while 180 (25.1%) required intervention. Treatment failure was associated with greater post-treatment residua thickness (mean 19.1 ± 9.1 mm vs. 10.4 ± 6.7 mm, P < 0.001). Residua thickness was an independent predictor of failure (adjusted odds ratio [aOR] 1.17, 95% confidence interval [CI]: 1.13-1.21, P < 0.001). ROC analysis identified an optimal cutoff of 14.9 mm, yielding 70% sensitivity and 81% specificity (area under the curve [AUC]: 0.835, 95% CI: 0.80-0.87) for predicting the need for surgical intervention.

Post-treatment residual thickness is a significant predictor of pharmacological treatment failure in early pregnancy loss, with a clinically relevant cutoff of approximately 15 mm. Histologic validation provides a promising framework for refining management protocols, emphasizing the need for further studies to establish robust predictive criteria.