Development and Evaluation of a Scoring System for the Expectant Treatment of Residual Tissue Expulsion after Medical Abortion for Patients with Missed Miscarriage, a Prospective Study

Abstract

Background: Missed miscarriage patients with residual tissue in the uterine cavity after medical abortion can be treated by surgery and expectant therapy. Because surgery may cause damage to the endometrium, expectant treatment is preferred clinically. However, the individual probability of expulsion of residual tissue from the uterus remains unelucidated. The present study used logistic regression analysis and nomogram to create a scoring system for quantitatively evaluating the individual probability of residual tissue expulsion in patients with missed miscarriage. Methods: A cohort of 126 patients with missed miscarriage who had residual tissue after medical abortion were included in the trial after receiving their informed consent. Of these patients, 102 and 24 patients had successful and failed expectant treatment, respectively. Results: Logistic regression analysis showed that gravidity, residual tissue size, and residual tissue with blood supply significantly affected the probability of expulsion of residual tissue after medical abortion. A special nomogram was constructed for predicting the probability of successful expulsion. At the maximum Youden index of 0.696, the area under the curve (AUC) of the receiver operating characteristic curve (ROC) was 0.849; this corresponded to a score of 77.78 and probability of residual tissue expulsion of 71%. Conclusion: A scoring system was established based on a nomogram. The success rate of residual tissue expulsion from the uterine cavity was significantly improved at the total score of 77.78 points after assigning influence weights to each influencing factor and an AUC of 0.849.