Maternal Hypertriglyceridemia: A Link Between Maternal Overweight-Obesity and Macrosomia in Gestational Diabetes

ObjectiveInfants born from overweight and obese mothers with glucose-controlled gestational diabetes (GDM) tend to be large-for-gestational age (LGA). It is hypothesized that this is due to an excessive rise in maternal triglyceride levels. MethodsTwo-hundred and seventy nine singleton GDM pregnancies were divided into three groups according to prepregnancy BMI: normal weight (BMI=20-24.9; n=128), overweight (BMI=25-29.9; n=105), and obese (BMI30; n=46). Individual z-scores (ZS) of maternal triglycerides and of newborn weight (NWZS) were calculated as deviations from published 50th percentiles. Mean z-scores (MZS) were the average of triglyceride ZSs. MZS of triglycerides, HbA1c and NWZS were compared. Variables are expressed as meanSD. ResultsIn the three groups respectively: LGA (%)=10.1%, 19.0% and 30.4% (P=0.015). Birth weight (g)=3274.2 +/- 501.3, 3342.4 +/- 620.2 and 3366.3 +/- 644.7 (R-SPEARMAN=0.111, P=0.027). HbA1c (%)=5.2 +/- 0.39, 5.3 +/- 0.50 and 5.4 +/- 0.47 (P=NS). Triglyceride MZS=1.20 +/- 1.13, 1.52 +/- 1.37 and 1.62 +/- 1.42 (R-SPEARMAN= 0.116, P=0.024). Correlations between triglyceride MZS and NWZS were, respectively: r=0.12 (P=NS), r=0.42 (P <0.001), and r=0.47 (P<0.001). ConclusionsIn overweight and obese GDM mothers, maternal triglycerides are partially responsible for LGA infants despite good maternal glucose control during pregnancy.