BACKGROUND/OBJECTIVES: The use of multimicronutrient (MMN) supplementation to reduce the burden of anaemia in non-pregnant women of reproductive age has been little studied, particularly in Africa. The objective of the study was to evaluate haematological outcomes in non-pregnant, rural Gambian women of reproductive age, receiving daily MMN supplements for 1 year. SUBJECTS/METHODS: The study in 293 women aged from 17 to 45 years old was nested within a double-blind, randomized placebo-controlled trial of periconceptional MMN supplementation [ISRCTN 13687662], using the United Nations International Multiple Micronutrient Preparation (UNIMMAP), received daily for 1 year or until conception. Red cell parameters and free erythrocyte protoporphyrin concentration were measured at baseline and after 12 months in those women who did not conceive. RESULTS: Anaemic women (haemoglobin concentration <12 g per 100 ml) were more likely to be older and in economic deficit at baseline. Mean change in haemoglobin concentration was +0.6+/-1.4 g per 100 ml in the intervention arm and -0.2+/-1.2 g per 100 ml in the placebo arm (P<0.001). After supplementation with MMN, the relative risk of anaemia (<12 g per 100 ml) was 0.59 (0.46, 0.76) compared with placebo. Anaemic subjects at baseline showed an increase in mean haemoglobin from 10.6 g per 100 ml to 11.8 g/l (P<0.001) after MMN supplementation. CONCLUSIONS: MMN supplementation should be considered as a strategy for improving the micronutrient and haematological status of non-pregnant women of reproductive age.