To explore the relationship between residual uterine septum and the length and width of uterine septum and its pregnancy outcome.

We collected 139 patients with uterine septum who underwent secondary hysteroscopy in Beijing Pinggu District Hospital and Tiantan Hospital affiliated to Capital Medical University from Jan. 2013 to Dec. 2019. All patients were treated by transcervical resection of septum (TCRS). They were followed up for 2-6 years. The predictive factors of residual septum were analyzed; Preoperative and postoperative pregnancy and obstetric outcomes in patients with septum residuals ≤0.5 cm and septum residuals >0.5 cm were analyzed.

There was no statistical significance in the length and width of the uterine septum and the residual septum. There were no statistically significant differences between the two groups of patients with septum residuals ≤0.5 cm and septum residuals >0.5 cm in age, number of births, abortions, infertility, infertility time, and classification of uterine septum, pregnancy rate, miscarriage rate, preterm birth rate, cesarean section rate, postoperative complications, placenta previa, and postpartum hemorrhage were not statistically significant, and the difference in term birth rate was statistically significant. No recent complication occurred in the two groups during and after surgery (P<0.05).

All patients with TCRS need second hysteroscopic examinations 2 months after operation to evaluate the condition of uterine cavity; more than 0.5 cm of residual septum should be removed again to improve pregnancy outcomes.