Heparin-Binding Angiogenic Factors (Basic Fibroblast Growth Factor and Vascular Endothelial Growth Factor) in Early Neonatal Life

This study investigated whether serum levels of the potent angiogenic factors basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), which are abundantly produced in utero by the placenta and fetal tissues, change after birth at term, consequent to diminished angiogenic but increased adaptational demands in extrauterine life. Moreover, whether serum levels of the above factors correlate with sex, birth weight, or mode of delivery was also evaluated. One milliliter of blood was drawn from 30 healthy, appropriate for gestational age, full-term infants on d 1 (N1) and 4 (N4) postnatally. In 10 of the above cases maternal and umbilical cord blood samples were also drawn. Serum was analyzed by enzyme immunoassays, using commercial kits. Levels of bFGF and VEGF were significantly lower in maternal serum than in umbilical cord (p = 0.02 and 0.036, respectively) or N1 (p = 0.009 and 0.006, respectively) and N4 serum (p = 0.009 and 0.006, respectively). Levels of bFGF in umbilical cord serum did not differ significantly from those in N1 and N4. In contrast, levels of VEGF rose in N1, differing significantly from levels in umbilical cord serum (p = 0.008). Both factors did not change from N1 to N4. Neither bFGF nor VEGF serum levels depended on sex, mode of delivery, or birth weight. In conclusion, bFGF levels in neonates do not differ from levels in fetuses, possibly reflecting diminished angiogenesis in extrauterine life, which already has started in utero. On the contrary, neonatal levels of VEGF rise significantly after birth, possibly signifying adaptation demands, in addition to angiogenesis, as VEGF is also considered a regulator of normal function.