Objective To assess the effects of vitamin A supplementation in women with anaemia during pregnancy.
Design Single-centre randomised controlled trial.
Setting Rural community in southern Malawi, central Africa.
Population Seven hundred women with singleton pregnancies at 12–24 weeks measured by ultrasound scan and with haemoglobin <11.0 g/dl by HemoCue screening method. Analysis was by intention to treat. All received iron and folate, and sulphadoxine/pyrimethamine for antimalarial prophylaxis.
Methods Women were randomised to receive oral supplementation with daily 5000 or 10 000 iu vitamin A, or placebo.
Main outcome measures Anaemia, as assessed by Coulter counter, severe anaemia, iron status and indices of infection.
Results Vitamin A deficiency was, in this rural population, less common than predicted. Vitamin A supplementation had no significant impact on anaemia, severe anaemia, iron status and indices of infection. Vitamin A stores were less likely to be depleted at the end of pregnancy in supplemented groups.
Conclusions Vitamin A supplementation programmes to reduce anaemia should not be implemented in similar antenatal populations in rural sub-Saharan Africa unless evidence emerges of positive benefit on substantive clinical outcomes. Introducing public health interventions of unknown benefit and with unclear biological mechanisms can divert scarce resources from clinical and social interventions more likely to impact maternal mortality.