Breast-milk sugar profiles
HMO concentration and composition in breast milk are highly variable and individual-specific. Little is known about how maternal health and environmental factors affect prenatal HMOs. To change this status quo, the HMO (Effect of physical activity in pregnancy on maternal and fetal human milk oligosaccharides) initiative tested maternal and foetal HMOs. The aim was to find biomarkers indicative of pregnancy outcomes and foetal developmental programming. To begin with, researchers established a high-performance liquid chromatography method with fluorescence detection for HMO identification and quantification. This highly sensitive method can quantify up to 18 HMOs per secretor blood group status based on the presence or absence of 2'Fucosyllactose and Lactodifucotetraose. Results were validated using mass spectrometry and enzymatic digest. The project recruited 27 healthy, normal-weight women for an observatory longitudinal cohort study throughout gestation to determine HMO profile variability. Scientists evaluated maternal HMO concentration in serum samples at four time points, the last time point being the delivery period. Results indicate that HMOs are detectable in maternal serum even in the first trimester, and their concentration increases as the due date approaches. During pregnancy, from a predominantly sialylated HMO profile, the levels of fucosylated HMO became significantly higher in the second trimester of pregnancy. Statistical analyses of maternal and foetal HMO profiles revealed that maternal metabolic status influences prenatal HMO concentration and composition. More specifically, maternal HMO could affect foetal outcome, but there were no significant indications of impact on foetal growth or body composition. The HMO study has determined prenatal HMO profiles in a healthy pregnancy cohort. This has laid the foundation for larger studies in the future to correlate non-invasive biomarkers in breast milk with diseases in neonates and lactating mothers. This includes detecting conditions such as pre-eclampsia and gestational diabetes. Such studies could help policymakers and public health agents implement pro-health lifestyle interventions that minimise the risk of aberrant foetal programming.
Keywords
Human milk oligosaccharides, breast milk, biomarkers, pregnancy, HMO, foetal outcome
