PURPOSE: to evaluate the importance of circulating maternal and fetal leptin in the healthy gestation, using its association with maternal, placental and fetal anthropometric variables, obtained at birth, and the relationship between the evaluated compartments. METHODS: in a transversal study a population of 33 single, healthy and term gestations was studied. The evaluated variables were maternal age, maternal weight, body mass index (BMF), weight of the newborn, placental weight, and placental index. Samples of maternal blood were immediately obtained before birth and from fetal umbilical cord blood at birth. Determination of serum leptin was performed using conventional radioimmunoassay. The relationships between serum leptin concentrations in maternal blood, umbilical artery and vein and the studied variables were assessed through linear regression. RESULTS: leptin levels were detected in the blood of all 33 pregnant women and their respective newborns, with maternal blood concentration (17.1±1.77 ng/mL) higher than that of umbilical vessels (vein: 9.0±1.16 ng/mL; artery: 8.23±1.02 ng/mL), p<0.0001. Leptin concentrations in the maternal blood were correlated with leptin concentrations in fetal blood (artery: coef. 0.63, p=0.037; vein: coef. 0.72, p=0.006). Regarding the anthropometric variables, leptin measured in the maternal blood was associated with initial and final maternal BMF (coef. 1.13; p=0.002; coef. 1,18, p=0.001) and cord leptin levels were correlated with the fetal weight at birth (vein: coef. 0.007, p=0.02; artery: coef. 0.006, p=0.02). CONCLUSION: there was a correlation between maternal and fetal leptin production and probably by the action of similar stimuli during gestation. Serum leptin was associated with the weight of the compartment where it circulates.
Fetal development; Leptin; Fetal blood; Fetal weight; Placentae; Normal pregnancy
