The docosahexaenoic acid (DHA) status of preterm infants (less than 32 wk gestation) was measured as the molar percent of DHA in individual red blood cell phospholipids: 1) in cord venous blood immediately following delivery, 2) after infants were receiving greater than 60 kcal X kg X day of energy from oral-gastric feedings, and 3) at a mean of 7 wk later. Infants on full feeding received either preterm human milk or formula. The DHA concentration of all phospholipid classes declined between birth and the time at which enteral feedings constituted the primary source of energy. Subsequent feeding with preterm human milk increased the molar percent of red blood cell phospholipid DHA, while DHA declined further in infants fed formula. Infants fed human milk compared to those fed formula had a significantly higher molar percent of DHA in all red blood cell phospholipids studied.