Leptin and gestational weight gain: Relation of maternal and cord blood leptin to birth weight

OBJECTIVES: To determine maternal serum leptin concentrations throughout no rmal pregnancy, as well as cord blood leptin concentration, and to correlat e serum and cord blood leptin levels with gestational weight gain and birth weight, respectively. METHODS: This study comprised 52 normal pregnant women, including 11 in the first, 19 in the second, and 22 in the third trimester, in addition to 30 healthy, fertile nonpregnant women of comparable age and with normal body m ass index (BMI). Maternal blood and fetal cord blood samples were withdrawn from the normal, healthy pregnant women and the nonpregnant controls for t he determination of serum leptin by a specific radioimmunoassay. RESULTS: Maternal serum leptin concentrations in the first trimester did no t differ significantly from those of healthy nonpregnant control subjects, whereas leptin concentrations in the second and third trimesters were eleva ted significantly. There were significant positive correlations between mat ernal serum leptin concentration and gestational age, gestational weight, a nd BMI. Cord blood leptin concentration correlated positively with birth we ight and third trimester maternal serum leptin. CONCLUSION: Elevated serum leptin is associated with maternal adiposity and risk of developing large for gestational age infants. Copyright (C) 1999 b y the Society for Gynecologic Investigation.