Adequacy of maternal pyridoxine supplementation during pregnancy in relation to the vitamin B6 status and growth of neonates at birth.

To evaluate the adequacy of maternal pyridoxine supplementation during pregnancy for both maternal and neonatal status at birth, vitamin B6 status, assessed by plasma pyridoxal phosphate (PLP), pyridoxal (PL) and total aldehyde vitamer (PLP + PL) concentrations, and the growth of neonates, including weight, length, head and chest circumferences, were examined for 209 neonates whose mothers were supplemented with 0, 1, 2 or 3 mg pyridoxine.HCl (PN.HCl)/d during pregnancy. Maternal PN.HCl supplementations were positively correlated to both maternal (r = 0.62) and cord (r = 0.78) plasma PLP concentrations (p < 0.0001). Mothers supplemented with 2 or 3 mg/d PN.HCl had significantly higher plasma concentrations of PLP and total B6 aldehyde vitamer in maternal and cord blood compared with those receiving 0 or 1 mg PN.HCl/d. A growth benefit for neonates whose mothers had maternal and cord plasma PLP concentrations > or = 40 nM was revealed by the maternal supplementation of 2 mg PN.HCl/d during pregnancy. Thus, in healthy pregnant women, according to our study, a daily supplement of 2 mg PN.HCl provides the adequacy of maternal and neonatal vitamin B6 status and the satisfactory growth of neonates at birth.