The role of vitamin A in nutritional anaemia : a study in pregnant women in West Java, Indonesia

Nutritional anaemia affects 50-70% of pregnant women in the developing world where vitamin A deficiency is also a problem. Since previous studies have indicated that vitamin A deficiency can be involved in the aetiology of nutritional anaemia, the role of vitamin A deficiency in nutritional anaemia in pregnant women has been investigated in West Java, Indonesia. Of the 318 normal pregnant women examined in a cross-sectional study, 49% were anaemic and, according to multiple criteria, 43% had iron-deficiency anaemia, 22% had iron-deficient erythropoiesis, and 7% were iron depleted. Based on serum retinol values, 2.5% of the women were vitamin A deficient and 31 % had marginal vitamin A status. After adjustment for gestational stage, parity and subdistrict, serum retinol concentrations were significantly positively associated ( p <0.01) with haemoglobin concentrations, haematocrit, and serum iron concentrations. In order to test whether the anaemia observed would respond to improvement in vitamin A supply, a randomised, double-masked, placebo-controlled field trial was carried out in which anaemic pregnant women in the same area were supplemented with vitamin A and iron. The women (n=251), aged 17-35 years, parity 0-4, gestation 16-24 weeks, and haemoglobin between 80 and 109 g/L were randomly allocated to four groups: vitamin A (2.4 mg retinol) and placebo iron tablets; iron (60 mg elemental iron) and placebo vitamin A; vitamin A and iron; or both placebos, all daily for 8 weeks. Maximum response in haemoglobin was achieved with both vitamin A and iron supplementation (12.78 g/L, 95% CI 10.86 to 14.70), with one-third of the response attributable to vitamin A (3.68 g/L, 2.03 to 5.33) and two-thirds to iron (7.71 g/L, 5.97 to 9.45). After supplementation, the proportion of women who became non-anaemic was 35% in the vitamin-A-supplemented group, 68% in the iron-supplemented group, 97% in the group supplemented with both, and 16% in the placebo group. In a subgroup (n=104) of the women in the intervention study, the intake of food and nutrients was also measured. The median daily intake of vitamin A, including provitamin A, was 1023 (10th and 90th percentiles; 65, 1914) μg retinol equivalent (RE). About 24% of the women had intakes below the daily intake of vitamin A recommended for pregnant women in Indonesia (700 μg RE). The suboptimal vitamin A status associated with nutritional anaemia suggests that measures to combat anaemia in pregnant women should involve improvement not only of iron status but also of vitamin A status.