LAUSR

OBJECTIVE An increasing number of women present pregnant having undergone bariatric surgery, a popular treatment for sustainable weight loss. The aim of the study was to investigate the effect, if any, of bariatric surgery on maternal and neonatal insulin resistance (IR) and neonatal body fat composition. METHODS Maternal IR, at 28 weeks of gestation during 2-h 75 g oral glucose tolerance test (OGTT), neonatal IR, from umbilical cord venous blood, and neonatal birthweight and body fat composition (calculated by measuring skin folds) at birth were evaluated in 41 post-bariatric and 82 pregnant women with similar early pregnancy body mass index but no history of such surgery. Insulin resistance was assessed using the homeostasis model assessment of IR (HOMA-IR). RESULTS In the post-bariatric surgery group, compared to the no surgery group, maternal HOMA-IR (1.15 [1.04-2.07] vs 2.20 [1.53-3.38]; p < 0.01), neonatal birthweight (p < 0.01) and body fat (p < 0.01) were significantly lower whereas neonatal cord HOMA-IR was similar (1.29 [0.65-2.39] vs 1.19 [0.46-1.93]; p = 0.49). In the no surgery group, there was a positive correlation between maternal and neonatal HOMA-IR (p = 0.03) and between neonatal HOMA-IR and body fat (p < 0.01). However, no such significant correlations were detected in the post-bariatric surgery group. CONCLUSION Pregnancy following bariatric surgery is associated with a reduction in maternal IR and altered neonatal body composition with significantly lower birthweight and adiposity but no improvement in cord IR.