Trimester-specific gestational weight gain in women with and without previous bariatric surgeries

Objectives: The study aimed 1) to compare trimester-specific and total gestational weight gain (GWG) between mothers who had undergone biliopancreatic diversion with duodenal switch (BPD) and two control groups of unoperated women and 2) to examine the associations between GWG, intrauterine fetal growth and neonatal birthweight.

Methods: This retrospective study included data collected in medical records of newborns and mothers from 3 groups: the first control group (PP) included mothers (n = 158) with a pre-pregnancy BMI similar to that of the surgical group (n = 63) and the second one (PS) included mothers (n = 85) with a pre-pregnancy BMI corresponding to that of the surgical group prior to BPD or a BMI > 40 kg/m². Trimester-specific GWG was obtained using linear interpolation and compared to the recommendations.

Results: Women exposed to BPD have an increased prevalence of insufficient weight gain in the second and third trimesters as well as for the whole pregnancy in comparison with women in the PP group. The weekly GWG rate in the third trimester was significantly lower in women exposed to BPD, compared to both control groups. Although the newborns of women with previous BPD were significantly smaller during pregnancy and at birth, no association was found with GWG.

Conclusion: Women exposed to BPD are at substantial risk of insufficient GWG, however, mechanisms and long-term impacts require further investigation.