Predicting pregnancy rate in women with tubal ligation after tubal anastomosis: A novel predictive nomogram

Abstract

Purpose This study aimed to develop and internally validate a novel nomogram predicting pregnancy rate in women with tubal ligation after tubal anastomosis. Methods We developed a prediction model based on a training dataset of 208 patients who underwent tubal anastomosis treatment between January 2012 and August 2020 in Sir Run Run Shaw Hospital of Zhejiang University. The Lasso regression model was used to optimize feature selection for the pregnancy rate risk model. The performance of the nomogram was assessed for its calibration, discrimination, and clinical usefulness. Internal validation was assessed. Results Predictors contained in the prediction nomogram included age, type of anastomosis, sterilization duration, time of conception, and Anti-mullerian hormone (AMH). The model displayed good discrimination with a C-index of 0.924 (95% confidence interval: 0.876–0.971) and good calibration. High C-index value of 0.879 could still be reached in the interval validation. Decision curve analysis showed that the pregnancy rate nomogram was clinically useful when intervention was decided at the pregnancy rate possibility threshold of 1%. Conclusion This novel pregnancy rate nomogram incorporating the age, type of anastomosis, sterilization duration, time of conception, and AMH could be conveniently used to predict the pregnancy rate in women with tubal ligation after tubal anastomosis.