The Impact of Breastfeeding on Maintaining Body Weight After Bariatric Surgery—A Retrospective Analysis of Maternal Outcomes of Bariatric Surgery and Pregnancy Study (MOMBARIS) Multicenter Data

Metabolic bariatric surgery (MBS) is the most effective obesity treatment. The increasing number of MBS among young patients has led to more post-bariatric pregnancies. Our study investigates how breastfeeding duration impacts postpartum weight retention and health outcomes for mothers and babies after MBS. MOMBARIS (Maternal Outcomes of Bariatric Surgery and Pregnancy Study) is a multicentre study. The population is derived from MOMBARIS 2, which focused on obstetric outcomes. It included patients who became pregnant following MBS, analysing pre-operative metrics, type of surgery, pregnancy details, and breastfeeding duration. Data analysis was conducted using Julius.ai. We analysed 156 patients post-MBS, with 148 pregnancies leading to childbirth. Among them, 131 had laparoscopic sleeve gastrectomy (LSG), 12 underwent Roux-en-Y gastric bypass (RYGB), and 5 had one anastomosis gastric bypass (OAGB). The mean age was 31.7 ± 5.45 years (range 19–48) with a pre-operative BMI of 43.9 kg/m2 ± 5.8 kg/m2 (range 31.9–68.8). The mean %EWL was 72% (± 28.6). Seventeen patients had multiple children. Breastfeeding results indicated that 116 patients (78.4%) initiated breastfeeding, with 40.5% continuing beyond 6 months. No significant differences were found in BMI metrics across breastfeeding groups. Bariatric outcomes (%EWL, %TWL) show no statistical difference based on breastfeeding patterns, nor does breastfeeding significantly affect weight loss maintenance post-surgery. Additionally, delaying pregnancy after surgery does not guarantee more significant weight loss.