1385-P: Associations between Maternal Metabolomic and Lipidomic Profiles across Gestation with Neonatal Birthweight in Type 1 Diabetes Pregnancy

Aims/Objectives: To describe the maternal-fetal metabolomic and lipidomic profiles and examine associations with neonatal birthweight in type 1 diabetes pregnancy. Methods: A longitudinal prospective study of 162 CONCEPTT mothers. 1049 maternal metabolites and 1041 lipids were analyzed at 12, 24 and 34 weeks gestation, in addition to 93 cord-blood samples using ultra-performance liquid chromatography-tandem mass spectroscopy. The effects on neonatal birth weight, classified as appropriate for gestational age (AGA) 10-90th percentile, large for gestational age (LGA) >90th percentile and extreme LGA (ELGA) >97.7th percentile were examined through ANOVA, principle component analysis and hierarchical clustering, adjusting for maternal BMI. Results: Significant gestational changes in the maternal metabolome and lipidomic profiles were observed. Metabolite changes associated with birthweight were modest in LGA, albeit more apparent in ELGA. At 24 and 34 weeks, glucose levels were significantly elevated and 1,5-anhydroglucitol (1,5-AG) significantly reduced in ELGA mothers. Triglycerides did not differ between AGA and LGA. Throughout pregnancy, many lipid classes were lower in LGA mothers, with modest increases in free fatty acids and acylcarnitine species at 34 weeks in ELGA. The distribution of lipid classes was significantly different between maternal and cord-blood samples, with most cord-blood lipids comparable between AGA, LGA and ELGA. There were some differences in the cord-blood steroid hormones and acylcarnitine species of ELGA neonates. Conclusions: Gestational changes in maternal-fetal metabolomic and lipidomic profiles are largely conserved across birthweight categories. Some differences in glucose handling, lipid homeostasis, steroid hormones and acylcarnitine species were apparent in maternal-fetal samples of ELGA neonates.