Placenta: a possible predictor of vitamin A deficiency

The objective of the present study is to assess the association between vitamin A deficiency (VAD) evaluated by serum retinol concentration from the mother and umbilical cord and placental concentration of retinol and carotenoids to propose placental values representative of deficiency. Two hundred and sixty-two puerperal women and their newborns were assessed. Concentration of serum and placental retinol and carotenoids was determined by the spectrophotometric method. Receiver operating characteristic (ROC) curve analysis was performed according to two cut-off points (0.70 and 1.05 mumol/l) to represent deficiency in the placental concentration. No difference between averages of placental retinol and carotenoids was observed in the puerperal women regardless of the cut-off point used to define VAD. In relation to the newborns, a decrease (P = 0.012) in placental retinol averages in individuals with VAD was observed when the 1.05 mumol/l cut-off point was adopted. In respect to the placental carotenoid averages, a decrease is observed for both the cut-off points (P = 0.013 and 0.019 for 1.05 and 0.7 mumol/l, respectively). The ROC curve results point to the value of 0.80 mumol/l as representing deficiency with greater values found for sensitivity (66.7 %), specificity (41.7 %) and accuracy (65 %) when the 0.70 mumol/l cut-off point was adopted. The results of the present study show an association between the placental concentration of retinol and carotenoids with clinical VAD, suggesting the need for further studies on more severe cases of deficiency.