Plasma and breast milk vitamin A as indicators of vitamin A status in pregnant women.

Breast milk vitamin A is not well characterized as an indicator of vitamin A status in women with infections. A controlled trial of vitamin A, 3 mg retinol equivalent/day, was conducted among 697 pregnant women with human immunodeficiency virus (HIV) infection in Malawi which allowed comparison of plasma versus breast milk vitamin A as indicators of vitamin A status. Retinol concentrations were measured in plasma at baseline (18-28 weeks) and 38 weeks gestation and breast milk at 6 weeks post-partum. Plasma alpha 1-acid glycoprotein (AGP) and C-reactive protein (CRP) were measured at baseline. Plasma retinol (geometric mean, SD) at 38 weeks was 0.72 (0.44, 1.18) and 0.61 (0.38, 0.98) mumol/L (P < 0.0002) and breast milk retinol was 1.32 (0.71, 2.43) and 0.95 (0.49, 1.82) mumol/L (P < 0.0001) in vitamin A and placebo groups, respectively. Women with elevated acute phase protein (AGP > 1 gm/L and/or CRP > 5 mg/L) at baseline who received vitamin A had significantly higher plasma and breast milk vitamin A at follow-up compared with placebo. Elevated acute phase proteins did not distinguish women with low body stores of vitamin A. Breast milk retinol appears to be a better indicator of vitamin A status than plasma retinol in women with infections.