[Impact on colostrum retinol levels of immediate postpartum supplementation with retinyl palmitate].

OBJECTIVE: To assess the effect of retinyl palmitate supplementation on colostrum retinol levels, investigating the influence of maternal variables (age, type of delivery, and biochemical nutritional status) on these levels.

METHOD: The study included 33 mothers receiving care at the Januário Cicco Maternity School, in the city of Natal, Rio Grande do Norte, Brazil. In the first hours after delivery, blood and colostrum samples were collected. Another colostrum sample was collected six hours after maternal supplementation with 200,000 IU of retinyl palmitate. Serum and colostrum retinol levels were determined by high-performance liquid chromatography.

RESULTS: The mean retinol level in colostrum before the supplementation was 110.8 +/- 82.3 microg/dL, and after supplementation it was 164.4 +/- 106.5 microg/dL (P < 0.025). Of the 33 mothers, 12 of them either did not respond to supplementation or had an increase of less than 10% in colostrum retinol levels; serum retinol in these women was significantly lower as compared to the responders (P = 0.024). In comparison to women with a normal delivery, the mothers who underwent cesarean delivery (64%) had lower serum retinol levels, but not lower colostrum retinol levels (P = 0.036). Maternal age did not influence retinol levels in either serum or colostrum.

CONCLUSION: The increase in colostrum retinol levels following vitamin A supplementation was sufficient to guarantee double the retinol requirements of a newborn infant.