Spontaneous mid trimester rupture in an unscarred complete septate uterus with gut loop prolapsed in left uterine cavity- A maternal near miss mortality. Background- Rupture uterus is the most dreaded obstetric complication- a direct cause of maternal near miss usually seen in third trimester or during labor with pre-existing risk factors. Spontaneous rupture during second trimester in an unscarred uterus with the gut prolapsed in left cavity of complete septate unscarred uterus with no history of instrumentation is rarest of rare. Case: A 26-year, G6 P4 L3 A1 with 6 months amenorrhea presented with acute-onset abdominal pain in shock. Emergency exploratory laparotomy was performed for a diagnosis of rup-tured uterus. A dead fetus was lying in the peritoneal cavity. There was an eight centimeters fundal rupture in uterus with massive haemoperitoneum. A 2.5cms thick long septum running from fundus till internal os with an 8cms loop of transverse colon densely adherent to myometrium of the left uterine cavity till internal OS was seen. After excision of septum, transverse colon prolapsed in left uterine cavity was separated with sharp dissection. Conservative approach with repair of uterus and bilateral tubal ligation was performed along with resuscitative measures. The patient recovered uneventfully. Conclusion: Spontaneous rupture of un-scarred septate uterus in a grand-multipara along with prolapse of the gut loop in the uterine cavity may occur even in the absence of any instrumentation/surgery. Early diagnosis of uterine anomaly, prompt resuscitation with blood products and emergency exploratory laparotomy are essential in suc-cessful management.