Abstract Study question Does hysteroscopic septoplasty improve reproductive outcome in patients who were diagnosed to have a septate uterus (SU) after a previous live birth? Summary answer This study suggests that hysteroscopic septoplasty improves the chance of a live birth in patients with both SU and a history of previous live birth. What is known already SU accounts for 50% of uterine anomalies and can be associated with adverse pregnancy outcomes. Many observational studies reported significant improvement in pregnancy outcomes following hysteroscopic septoplasty. However, some investigators have reported good reproductive outcome among women with SU without surgical interventions. A recent randomized controlled trial, albeit with a small sample size, reported no difference in reproductive outcomes between patients who underwent hysteroscopic septoplasty and those who had no surgery (Rikken 2021). Therefore, more studies are needed to be able to counsel patients with SU presenting with reproductive failure, especially those with a history of a previous live birth. Study design, size, duration This retrospective study included 114 patients who had a previous live birth and subsequently complained of reproductive failure. A SU was diagnosed during their work up between 2005-2022. Patients presented with secondary infertility (98.3%) or with recurrent pregnancy loss (RPL) [1.7%]. Forty-two patients presented with both secondary infertility and RPL (36.8%). Participants/materials, setting, methods Diagnosis of SU was suspected on transvaginal 3D ultrasound scan and was confirmed on a diagnostic hysteroscopy at an infertility clinic affiliated with an academic hospital. Patients were offered the option of hysteroscopic septoplasty or expectant management. Infertility treatment options depended on the underlying etiology and included spontaneous conception, oral fertility medications, intrauterine insemination, and in-vitro fertilization/embryo transfer. Eighty-two patients underwent hysteroscopic septoplasty (Group 1), while 32 patients declined surgery (Group 2). Main results and the role of chance There were no significant differences in mean age (years), BMI (Kg/m2), infertility duration, baseline FSH levels (mIU/mL), number of miscarriages, and gestational age at delivery before treatment between the two groups. There were no significant differences in incidence of ≤ 3 or ≥ 3 pregnancies, nor incidence of one live birth or > 1 live birth between the two groups. There were no significant differences in the underlying etiology, except for a significantly higher incidence of endometriosis (P = 0.004) and diminished ovarian reserve (P = 0.04) in Group 1 compared to Group 2. There were no significant differences in the incidence of partial septate uterus (PSU) [angle of indentation <90 degrees] and complete septate uterus between the two groups. However, there was significantly lower incidence of PSU with angle of indentation > 90 degrees (P = 0.028) and higher mean septum length in mm (18.9±1.0 vs 13.8±1.1, P = 0.024) on hysteroscopy in Group 1 compared to Group 2. After treatment, there were significantly higher pregnancy (68.3% vs 37.5%, p = 0.003) and live birth (61.7% vs 25%, P = 0.000) rates, but no significant difference in miscarriages (4.9% vs 6.3%), preterm birth (14% vs 25%) rates, or method of pregnancy in Group 1 compared to Group 2. Limitations, reasons for caution Our study has limitations being retrospective in nature with a small sample size. Therefore, more studies are required to support our findings. However, our pilot study explored management options in a particular group of patients with SU who initially proved their fertility and subsequently presented with reproductive failure. Wider implications of the findings Our data support the notion that patients with SU can have a normal reproductive outcome, although those who undergo septoplasty are expected to have a better chance of conception and live birth. During counselling of patients with SU, both surgical and expectant management can be offered. Trial registration number not applicable