Objective: The aim was to investigate the overall postoperative complication rate within 90 days following ileal pouch-anal anastomosis (IPAA), with or without a diverting stoma, together with complications 30 days after stoma closure and overall pouch failure rate.

Methods: This was a retrospective chart review including IPAA patients with or without a diverting loop-ileostomy for ulcerative colitis (1 January 1983 to 31 December 2015). Demographic data and postoperative complications were retrieved and recorded.

Results: A total of 434 patients were included. A diverting loop-ileostomy was performed in 348 patients (80%). Baseline data were similar in the two groups except for body mass index (BMI) and the ratio of women, which were significantly higher in the group without a protective ileostomy. Overall 90-day complication rate after IPAA [Clavien-Dindo (CD) > 2] was similar in the two groups. Clinical anastomotic leaks (CD > 2) were higher in patients without a diverting stoma (9.3% vs 1.7%) (P = 0.002). The odds ratio for leakage after adjustments (age, gender, immune-modulating medicine and BMI) was 5.0 for omitting a diverting stoma (P = 0.004). Complications (CD > 2) after loop-ileostomy closure were seen in 61 cases (14.1%). Omitting a diverting stoma at IPAA demonstrated a non-significant odds ratio of 1.04 (0.46, 2.38) (P = 0.924) for pouch failure after adjustments (age, gender, immune-modulating medicine, BMI, time from pouch formation and clinical leakage).

Conclusions: The overall postoperative surgical and medical complication rate within 90 days after IPAA was similar in the group with and without diverting stoma. Postoperative complication rate after reversal was 14%. Omitting a diverting stoma at IPAA demonstrated an increased risk of leaks but no significant risk of long-term pouch failure.