To determine the influence of the prenatal long-chain polyunsaturated fatty acid (LCP) supply on prenatal growth and on postnatal LCP levels, we studied 52 preterm infants and assessed the relations between the LCP status at birth (reflecting the prenatal LCP supply), gestational age and prenatal growth, and the relation between the LCP status at birth and at 37 to 42 weeks of gestational age. After a correction for gestational age at birth, significant relations (p < or = 0.05) were observed between anthropometric measurements at birth (weight, head circumference, and length) and LCP levels in the umbilical artery wall, the LCP content of which reflects the long-term fetal LCP status. Independent of the neonatal diet (human milk or formula), LCP levels in erythrocyte phospholipids at term were positively related to levels in the umbilical artery wall (docosahexaenoic acid (22:6n-3): p < or = 0.0003; arachidonic acid (20:4n-6): p = 0.02). Postnatal diet significantly influenced LCP levels in plasma phospholipids at term (docosahexaenoic acid: p < or = 0.004; arachidonic acid: p = 0.02); formula-fed infants had lower values. We conclude that the LCP status of preterm infants at birth is related to prenatal growth. Moreover, next to the postnatal enteral diet, the LCP status at birth significantly affects LCP levels at term postconceptional age. This finding may warrant further studies of the effects of essential fatty acid-enriched maternal diets during pregnancy on the neonatal LCP status at birth.