Abstract

Changes in total lipid content, total cholesterol content and fatty acid composition of preterm milk were investigated during early lactation. Milk samples were collected from Korean mothers of 16 premature(34 to 36 weeks gestation age) infants on day 2 to 5(colostrum) and at 6 weeks(mature) postpartum. We estimated the lipid nutrition of preterm milk by comparing with the lipids of term milk. The total lipid content of preterm colostrum was significantly lower than the lipid content of preterm mature milk(p<0.001). Lipid content, determined gravimetrically in colostrum and matured milk, was 1.50g/이 and 3.2g/dl, respectively. Also the total cholesterol content(mg/dl) in preterm milk tends to increase from 14.16mg/dl to 15.20mg/dl, while the total cholesterol(mg/g lipid) concentration higher significantly in colostrum(12.36mg/g) than in mature(5.73mg/g)(p<0.001). The total unsaturated fatty acid contents in preterm milk were higher in colostrum than in mature milk and the total saturated fatty acids were higher in mature milk. The average DHA contents of colostrum and matured milk was 0.64%, 0.53% and the P/M/S ratio of preterm milk were 0.63 : 1.05 : 1.00, 0.47 : 0.79 : 1.00, respectively. Also, $\omega$6/$\omega$3 ratio of preterm milk were 2.35 in colostrum and 5.81 in mature. Therefore, colostrum in preterm milk contained higher amounts of $\omega$3 PUFA than mature milk. The levels of total lipid in preterm milk were higher than term milk. Also, preterm milk is richer in cholesterol, and long chain polyunsaturated fatty acid than term. It appears that the milk secreted by mothers who delivered prematurely differs from milk in several important respect. These components may serve as precursors for membrane, myelin development in the preterm infants. Therefore, it would be necessary to study further into the machanism of how the gestation age might affect to the lipid composition in human milk. These data may provide a basis for better construction of infant formaulas to provide more adequately for the lipid requirements of the Korean premature infant.

Keywords

• preterm milk;
• total lipid;
• total cholesterol;
• fatty acids