8.1 The association of maternal characteristics and macronutrient intake in pregnancy with neonatal body composition

Background The in utero environment has been found to affect fetal development however many of the mechanisms by which this occurs remain unknown. The aim of this study was to examine the association between maternal dietary macronutrient intake and lifestyle in pregnancy and neonatal body composition. Methods This was an analysis of 749 infants from the ROLO study (Randomised cOntrol trial of LOw glycaemic index diet versus no dietary intervention to prevent recurrence of fetal macrosomia). Food diaries and food frequency, lifestyle and exercise questionnaires were completed during pregnancy. Maternal anthropometry was measured throughout pregnancy and neonatal anthropometry was measured at birth. Results Multiple linear regression analysis revealed the main maternal factor associated with increased birth weight was gestational weight gain R2 adj 23.3% (F = 11.547, p < 0.001). The main maternal factor associated with increased birth length was non-smoking status R2 adj 27.8% (F = 6.193, p < 0.001). Neonatal central adiposity determined using waist:height ratio was negatively associated with maternal age, and positively associated with the following maternal parameters: smoking status, pre-pregnancy arm circumference, percentage energy from saturated fat in late pregnancy, postprandial glucose and control group membership. There was no association between neonatal anthropometry and maternal “healthy diet” clusters or adherence to a DASH diet. Conclusions Maternal low glycaemic index diet in pregnancy was found to have a beneficial effect on neonatal central adiposity. Additionally maternal dietary fat intake and late pregnancy postprandial glucose were positively associated with central adiposity, highlighting the important role of a healthy diet in pregnancy in promoting normal neonatal adiposity.