Surgical complications during pregnancy following bariatric surgery: a Belgian nationwide population-based study

Objective: To determine the incidence and clinical characteristics of surgical complications during pregnancy in women with a history of bariatric surgery. Design: A nationwide, prospective, population-based cohort study. Setting: High-risk obstetric care in Belgium: 67.6% of maternity units participated, covering 65% of all births in the study period. Participants: Pregnant women with a history of bariatric surgery presenting with a surgical complication (internal hernia, intussusception, volvulus or adhesions; anastomotic ulcer or abscess; gastric band slippage; or incisional hernia) between January 2021 and December 2022. Results: Thirty-three women experienced 35 surgical complications. Internal herniation was most common (n=25), predominantly following Roux-en-Y gastric bypass. Mean gestational age at diagnosis was 27+6 weeks. All women underwent surgical exploration within 24 hours; bowel resection was required in two cases. Caesarean section occurred in 48.5%, with 13 preterm births and one neonatal death. One woman required intensive care. No maternal death occurred. Conclusion: Surgical complications following bariatric surgery in pregnancy are uncommon but carry significant obstetric risks. All observed complications occurred after procedures involving intestinal rerouting, predominantly Roux-en-Y gastric bypass. Prompt surgical management was associated with low maternal morbidity and no mortality, but frequently resulted in preterm birth and emergency caesarean section. These findings highlight the need for a low threshold for surgical evaluation of abdominal pain in pregnant women with previous bariatric surgery and suggest that procedure type is relevant when counselling women of reproductive age.