The randomized trial of over 125,000 women, published in JAMA, found that despite evidence to suggest that the prevention of vitamin A deficiency among women in developing countries may improve maternal and infant survival, the use of weekly vitamin A or beta carotene supplements in pregnant women had no effect on all-cause maternal, fetal, or infant mortality.
“Supplementation of vitamin A and beta carotene in pregnant women in Bangladesh did not reduce all-cause maternal, fetal, or infant mortality,” said the authors, led by Dr Keith West Jr from Johns Hopkins University, USA.
However the authors added that irrespective of its effects on mortality,“achieving maternal adequacy in vitamin A through diet, supplementation, or fortification is an important public health goal."
Maternal vitamin A deficiency is a widespread problem in low-income countries, with the World Health Organization estimating that approximately 20 million pregnant women are vitamin A deficient globally.
Such deficiency is associated with night blindness, which is linked to increased risks of maternal anemia, illness and death – suggesting that preventing vitamin A deficiency could improve maternal survival.
Previous research has supported the notion that vitamin A supplementation can decrease rates of maternal, fetal, and infant deaths.
“Evidence of such an effect has been reported in rural Nepal, where a randomized controlled trial demonstrated a decrease of approximately 44 per cent in mortality related to pregnancy following continuous, weekly receipt of vitamin A or beta carotene during the reproductive years at dosages approximating a recommended daily allowance,” said the authors.
Given the importance of reducing mortality rates, further intervention trials using vitamin A have looked to back up these findings.
One such trial, conducted in Ghana, West Africa, (REF) reported no effect from weekly supplementation on all-cause maternal mortality, noted the authors.
The new study assessed the effect of supplementation with vitamin A or beta carotene on pregnancy-related maternal, fetal, and early infant mortality in Bangladesh.
Study groups were randomized for pregnant women to receive a weekly supplementation of either 7000 micrograms retinol equivalents as retinyl palmitate, 42 mg of all-trans beta carotene, or a placebo.
Compared to placebo or beta carotene supplementation, the authors reported that vitamin A supplementation increased plasma retinol concentrations and reduced, but did not eliminate, night blindness.
However they found that for mortality outcomes, neither of the supplement group outcomes was significantly different from the placebo group results.
Source: Journal of the American Medical Association (JAMA)
Volume 305, Issue 19, Pages 1986-1995
“Effects of Vitamin A or Beta Carotene Supplementation on Pregnancy-Related Mortality and Infant Mortality in Rural Bangladesh A Cluster Randomized Trial”
Authors: K.P. West Jr, P. Christian, A.B. Labrique, M. Rashid, A.A. Shamim, R.D.W. Klemm, et al