During pregnancy, essential long-chain polyunsaturated fatty acids (LCPUFAs
) play important roles as precursors of prostaglandins and as structural el
ements of cell membranes. Throughout gestation, accretion of maternal, plac
ental, and fetal tissue occurs and consequently the LCPUFA requirements of
pregnant women and their developing fetuses are high. This is particularly
true for docosahexaenoic acid (DHA; 22:6n-3). The ratio of DHA to its statu
s marker, docosapentaenoic acid (22:5n-6), in maternal plasma phospholipids
decreases significantly during pregnancy. This suggests that pregnancy is
associated with maternal difficulty in coping with the high demand for DHA.
The DHA status of newborn multiplets is significantly lower than that of s
ingletons; the same is true for infants of multigravidas as compared with t
hose of primigravidas and for preterm compared with term neonates. Because
the LCPUFA status at birth seems to have a long-term effect, the fetus shou
ld receive an adequate supply of LCPUFAs. Data from an international compar
ative study indicated that, especially for n-3 LCPUFAs, the fetus is depend
ent on maternal fatty acid intake; maternal supplementation with LCPUFAs, t
heir precursors, or both increased LCPUFA concentrations in maternal and um
bilical plasma phospholipids. However, significant competition between the
2 LCPUFA families was observed, which implies that effective supplementatio
n requires a mixture of n-6 and n-3 fatty acids. Further research is needed
to determine whether higher LCPUFA concentrations in plasma phospholipid w
ill have functional benefits for mothers and children.