Plasma and red cell folate values in newborn infants and their mothers in relation to gestational age.

The plasma and red blood cell folate concentrations have been studied in 344 newborn infants at 20 to 43 weeks of gestation and in 286 of their mothers at delivery. Folic acid supplementation was no given to the mothers during pregnancy. The mothers had no signs of folate deficiency as judged from their plasma and red blood cell folate concentrations and the red blood cell picture. The infants had significantly higher plasma folate concentrations than in adult control subjects, and six to eight times higher plasma folate concentrations than found in their mothers throughout the observation period. The red cell folate concentrations in the infants were significantly higher than in adult control subjects, and the concentrations were about two times higher than found in their mothers until 34 to 37 weeks of gestation. Term infants had significantly higher red cell folate concentrations than infants of lower gestational age. During the last weeks of pregnancy an increased transfer of folate to the fetus probably takes place.