The relationship between maternal and neonatal umbilical cord plasma homocyst(e)ine suggests a potential role for maternal homocyst(e)ine in fetal metabolism.
OBJECTIVE
Data on fetal blood homocyst(e)ine concentrations are not available. We tested the hypothesis that homocyst(e)ine crosses the maternal/placental/fetal interphases and is sequestered by the fetus.


METHODS
The concentration of homocyst(e)ine was determined at parturition in peripheral venous plasma from 35 nulliparous healthy pregnant women and umbilical arterial and venous plasma from their conceptus.


RESULTS
Findings demonstrated a descending concentration gradient of plasma homocyst(e)ine from maternal vein to umbilical vein and to umbilical artery; the decrease at each interphase approximated 1 micromol/L. The neonate weight and gestational age were inversely related to maternal homocyst(e)ine concentrations.


CONCLUSIONS
The umbilical vein to umbilical artery homocyst(e)ine decrement suggests that uptake of homocyst(e)ine occurs in the fetus. The likely incorporation of homocyst(e)ine into the fetal metabolic cycle may implicate maternal homocyst(e)ine as having a potential nutritional role in the fetus. Further studies are required to explain the role of homocyst(e)ine in fetal metabolism and development.
Malinow
M R
MR
Division of Pathobiology and Immunology, Oregon Regional Primate Research Center, Oregon Health Sciences University, Beaverton 97006-3448, USA.
Rajkovic
A
A
Duell
P B
PB
Hess
D L
DL
Upson
B M
BM
D000328:Adult; D005260:Female; D005312:Fetal Blood / Q000378:metabolism*; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood*; D006711:Homocystine / Q000097:blood*; D006801:Humans; D007231:Infant, Newborn; D007743:Labor, Obstetric; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D012016:Reference Values; D014469:Umbilical Arteries; D014471:Umbilical Veins
D006710:Homocysteine; D006711:Homocystine; D005492:Folic Acid