A novel method for typing of cesarean scar pregnancy based on size of cesarean scar diverticulum and its significance in clinical decision-making

Aim There is currently no universally accepted method for typing of cesarean scar pregnancy (CSP) to guide the choice of treatment approach. We introduce a new method for typing CSP and investigate its clinical significance. Method Clinical data of 198 patients with CSP were collected and analyzed. The patients were divided into three types according to the size of their cesarean scar diverticula (CSD), measured by magnetic resonance imaging: type I (size of CSD <= 40 mm), type II (40 mm < size of CSD <= 70 mm) and type III (size of CSD >70 mm). Results With increase in the type level, the risk of adverse events increased significantly (chi(2) = 36.345, P = 0.000). There was a significant difference in the choice of the treatment approaches in various types of the patients (chi(2) = 27.106, P = 0.000). With increase in the type level, the invasiveness level of the treatment approach increased significantly (R = 0.405, P = 0.000). Further analysis found two other factors that influenced treatment choice. Conclusion Our study, for the first time, demonstrates the value of size of CSD in typing of CSP and, thereby supplements the CSP typing system with a novel quantitative indicator. This typing method is of significance for evaluation of risk of CSP and guiding the choice of treatment approach. This typing method, combined with the two features of cesarean scar thickness and lesions protruding outside the uterine contour, will improve the risk assessment of CSP and the rationale of treatment plan formulation for this condition.