Maternal mid-pregnancy serum triglyceride levels and neonatal birth weight

Abstract

Although disturbances in maternal glucose metabolism and resultant fetal hyperinsulinemia are known to significantly impact fetal overgrowth, it has been suggested that other fuels such as lipids and amino acids may be the determinants of fetal growth in nondiabetics. Maternal serum lipid levels increase in mid to late pregnancy; and in women with gestational diabetes, elevated triglycerides were significantly associated with birth weight corrected for gestational age. Although the role of maternal hyperlipidemia in fetal growth is not known, maternal fasting serum triglyceride levels at 24 to 32 weeks of Pregnancy were shown to be significantly and positively associated with neonatal weight at term,independent of maternal prepregnancy obesity, weight gain during pregnancy, or mid-pregnancy plasma glucose levels (either fasting or postprandial) in Japanese and white women. The aim of the present study was to determine the relationship between maternal mid-pregnancy serum lipid levels and neonatal birth weight in our region. Fasting levels of serum triglycerides and total cholesterol were evaluated in 108 consenting consecutive women who attended for prenatal care with a singleton pregnancy between 24 to 34 weeks and who had abnormal results on the glucose challenge test (plasma glucoseN140 mg/dL) and normal results from the oral 100 g 3-hour glucose tolerance test. Women with antiphospholipid antibody syndrome, hypertension, or thyroid disorder were excluded. The relationship between mid-pregnancy triglyceride and total cholesterol values and neonatal birth weight was determined according to fasting glucose, body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) and pregnancy weight gain—with 95 mg/dL, 25, and 10 kg as the cut-off values, respectively. The relative risk of having heavier babiesweighing 3.5 kg or greater was 2 (95% CI, 0.9–4.2) for women with hypertriglyceridemia and 2.6 (95% CI, 0.78–8.4) when controlled for fasting glucose, BMI, and pregnancy weight gain. When studied together, the combination of hypertriglyceridemia, fasting hyperglycemia, and higher BMI was a significant predictor of heavier neonates. It is important to note that the higher relative risk for heavier babies in women with hypertriglyceridemia persisted even when the variables such as greater BMI, greater pregnancy weight gain, and hyperglycemia were accounted for. With a combination of greater BMI and fasting hyperglycemia, women with hypertriglyceridemia had a much higher relative risk for heavier babies (RR 9.7; 95% CI, 1.7–62.6).