Night blindness during pregnancy and subsequent mortality among women in Nepal: Effects of vitamin A and beta-carotene supplementation

Night blindness due to vitamin A deficiency is common during pregnancy amon g women in Nepal. The authors assessed the risk of maternal death during an d after a pregnancy with night blindness among women participating in a clu ster-randomized, placebo-controlled vitamin A and p-carotene supplementatio n trial in Nepal from July 1994 to September 1997. Subjects were 877 women with night blindness and 9,545 women without night blindness during pregnan cy. Women were followed from the time they declared that they were pregnant through the end of the study, representing a median follow-up of 90 weeks (interquartile range: 64-121 weeks). Mortality of night-blind women in the placebo group was 3,601 per 100,000 pregnancies. In comparison, the relativ e risk of dying among nonnight-blind women in the placebo group was 0.26 (9 5% confidence interval (CI): 0.13, 0.55), and the relative risk among women with or without night blindness in the vitamin A/beta-carotene group was 0 .32 (95% CI: 0.10, 0.91) and 0.18 (95% Cf: 0.09, 0.36), respectively. Night -blind women were five times (35% CI: 2.20, 10.58) more likely to die from infections than were women who were not night blind. These findings show th at night blindness during pregnancy is a risk factor of both short- and lon g-term mortality among women. Vitamin A/beta-carotene supplementation ameli orates this risk to a large extent.