Maternal obesity is associated with changes in HMO concentrations that are associated with infant adiposity.
Infant intakes of 3-fucosyllactose, 3-sialyllactose, 6-sialyllactose, disialyllacto-N-tetraose, disialyllacto-N-hexaose, and total acidic HMOs were positively associated with infant growth over the first 6 M of life. Maternal BMI was positively associated with lacto-N-neotetraose, 3-fucosyllactose, 3-sialyllactose and 6-sialyllactose and negatively associated with disialyllacto-N-tetraose, disialyllacto-N-hexaose, fucodisialyllacto-N-hexaose and total acidic HMOs concentrations at 2 M. Maternal obesity was associated with lower concentrations of several fucosylated and sialylated HMOs and infants born to women with obesity had lower intakes of these HMOs. Linear regressions and linear mixed-effects models were conducted examining the relationships between maternal BMI and HMO composition and HMO intake and infant growth over the first 6 M, respectively. Infant HM intake, anthropometrics and body composition were assessed at 2 M and 6 M postpartum. Human milk (HM) samples collected at 2 months (2 M n = 194) postpartum were analyzed for HMO concentrations via high-performance liquid chromatography. We aimed to quantify the composition of HMOs of women with normal weight (18.5–24.9 kg/m 2), overweight (25.0–29.9 kg/m 2), or obesity (30.0–60.0 kg/m 2) and determine the effect of HMO intake on infant growth. Human milk oligosaccharides (HMOs) are bioactive molecules playing a critical role in infant health.