Influence of postpartum supplementation with vitamin A on the levels of immunoglobulin A in human colostrum.

To evaluate the influence of supplementation with retinyl palmitate in the immediate postpartum period on the levels of secretory immunoglobulin A (SIgA) in colostrum. A clinical trial was conducted among 96 recently-delivered mothers treated at a public maternity hospital, divided into control group, which was not supplemented (n = 44), and test group, supplemented on the first day postpartum (n = 52). Samples of 2 mL of colostrum were collected on the first 2 days postpartum. SIgA was measured by turbidimetry and data were analyzed by the Student t test. Before supplementation, the average SIgA was 829.1±337.6 mg/dL in the control group and 827.3±249.8 mg/dL in the test group (p = 0.52). After supplementation, the average SIgA was 343.9±177.2 mg/dL in the unsupplemented group and 501.2±54.5 mg/dL in the supplemented group (p < 0.00001). The colostrum of women supplemented with retinyl palmitate has higher levels of SIgA, which suggests that the production of antibodies is modulated by vitamin A.