Fatty acids composition of human milk fed to small for gestational age infants

Objectives: To test the null hypothesis that mothers of asymmetric small for gestational age (SGA) infants produce milk with fatty acids composition similar to that of lactating mothers of appropriate-for-gestational-age (AGA) infants. Methods: We obtained human milk (HM) from 2 groups of lactating volunteers that gave birth to asymmetric SGA (study group) or AGA infants (control group). Each mother was asked to contribute by manual expression at least one of 3 samples: first 72 hours after labor (colostrum), day 2-7 postpartum (transitional milk) and 14 days post partum (mature milk). After lipid extraction using Folch's cold-extraction procedure fatty acids were analyzed using gas chromatography. Results: A total of 108 samples were obtained in 60 women. In univariate analysis, there were no significant differences in any of the fatty acids concentrations examined between groups. This remained true when timing of the sample (colostrum, transitional or mature milk) or gestational age were introduced as confounders in analysis of variance (general linear model). Conclusion: Fatty acid composition of human milk is not affected by whether or not the infant was fetal growth restricted. We suggest that mothers of SGA infants may be reassured about the fat quality of their milk.