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Published on: December 16, 2015
Breast milk retinol concentration in mothers of preterm newborns
Mayara Santa Rosa Lima1, Karla Danielly da Silva Ribeiro1, Jeane Franco Pires2
1Department of Nutrition, Center of Health Sciences, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
Background:
Preterm newborns have low vitamin A reserves at birth, which increases their risk of morbidity and mortality. In the absence of supplementation, breast milk is the only source of this nutrient for exclusively breastfed infants.
Aims:
To assess retinol concentration in preterm milk and the relationship between this retinol concentration and lactation phase, degree of prematurity, and maternal serum retinol level.
Study Design:
Longitudinal study.
Subjects:
Fifty-eight preterm mothers.
Outcome Measures:
Colostrum (1-3d), transitional (7-15d), and mature human milk (30-55d) samples were collected. Maternal blood was collected once at postpartum. Retinol level was measured using high-performance liquid chromatography.
Results:
Milk retinol concentration was statistically different between lactation phases (p<0.001): 2.84±1.05μmol/L in colostrum (58), 3.47±1.28μmol/L in transitional (58), and 2.03±0.61μmol/L in mature milk (30). No difference was found in milk retinol levels between groups with different degrees of prematurity (p>0.05). Maternal serum retinol (1.82±0.50μmol/L) did not correlate with milk levels (p>0.05).
Conclusions:
Retinol level in preterm milk seems to be independent of the degree of prematurity and maternal serum status. A significant increase in micronutrient levels in transitional milk was observed, which is likely to contribute to reserves in the premature liver.
