Factors associated with tubal obstruction and development of a preliminary prediction model following laparoscopic tubal fenestration and embryo removal in patients with tubal pregnancy: a single-center exploratory study

To identify factors associated with tubal obstruction following laparoscopic tubal fenestration and embryo removal in patients with tubal pregnancy, and to develop a preliminary prediction model based on these factors. Clinical data of 310 patients who underwent laparoscopic tubal fenestration and embryo removal for tubal pregnancy at the Third Affiliated Hospital of Zhengzhou University between June 2020 and June 2025, and subsequently received hysterosalpingography, were retrospectively collected. Patients were randomly divided into a training set ( n = 217) and a validation set ( n = 93) using a 7:3 ratio. Based on hysterosalpingography results, the training set was further divided into a patent group ( n = 135) and an obstruction group ( n = 82). Multivariate logistic regression analysis was used to identify influencing factors for postoperative tubal obstruction. A nomogram prediction model for postoperative tubal obstruction was constructed using the R language, and its performance was evaluated through internal split-sample validation. The preoperative β-hCG level (100 IU/L), maximum diameter of pelvic fluid (mm), and the proportion of pregnancies located in the interstitial and isthmic portions of the fallopian tube were significantly higher in the obstruction group compared to the patent group, while the diameter of the tubal mass was smaller. These differences were statistically significant (all P < 0.05). Logistic regression analysis indicated that preoperative β-hCG level (100 IU/L), site of tubal pregnancy, maximum diameter of pelvic fluid (mm), and diameter of the tubal mass (mm) were independently associated with postoperative tubal obstruction ( P < 0.05). A nomogram was established using these factors. The area under the receiver operating characteristic curve (AUC) for the training set was 0.824 (95% CI: 0.770–0.879), indicating promising discriminatory ability within this exploratory cohort. Preoperative β-hCG level (100 IU/L), diameter of the tubal mass (mm), site of tubal pregnancy, and maximum diameter of pelvic fluid (mm) were identified as factors potentially associated with tubal obstruction in this single-center exploratory study. The nomogram developed from these factors demonstrated acceptable predictive performance in internal validation and may serve as a preliminary tool for preoperative risk estimation. However, external validation in independent multicenter cohorts is required before clinical implementation. For patients with small tubal masses who opt for fertility‑preserving surgery, thorough preoperative counseling regarding the risks of tubal stenosis, obstruction, hydrosalpinx, and recurrent ectopic pregnancy is essential, and postoperative HSG evaluation at 3 months may be considered as part of routine follow-up.