Effect of amaranth flatbread on maternal anthropometry during pregnancy: Evidence from a cluster-randomized controlled trial in Southern Ethiopia.

Abstract

Maternal undernutrition and iron deficiency anemia (IDA) remain major public health challenges in Ethiopia, contributing to adverse pregnancy outcomes and poor maternal health. Amaranth, a nutrient-dense pseudocereal, has demonstrated potential to improve maternal nutritional status, yet evidence from rigorous trials is limited. To evaluate the effect of amaranth grain flatbread on maternal anthropometric indicators - mid-upper arm circumference (MUAC), body mass index (BMI), and gestational weight change (GWG) - as proxies for overall nutritional status among pregnant women in Hawela Lida district, Southern Ethiopia. A parallel-group, two-arm cluster randomized controlled trial was conducted from September 2024 to February 2025. Pregnant women with mild-to-moderate anemia, residing in Hawela Lida district for at least six months, were enrolled before 12 weeks of gestation and randomly allocated to receive either 200 g/day of amaranth-chickpea flatbread (intervention, n = 153) or maize flatbread (control, n = 153) for six months. Anthropometric measurements (MUAC, GWG, BMI) were collected at baseline and endline. Multilevel linear regression models adjusted for individual- and community-level covariates were used to estimate intervention effects. Of the 306 participants, 293 (95.8%) completed the study. At endline, women in the intervention arm had significantly higher mean MUAC (26.1 ± 1.2 cm vs 24.3 ± 1.4 cm; adjusted β = 1.72, 95% CI: 1.48-1.96), BMI (23.8 ± 1.5 kg/m2 vs 21.9 ± 1.6 kg/m2; adjusted β = 1.89, 95% CI: 1.62-2.16), and GWG (8.4 ± 1.2 kg vs 6.1 ± 1.4 kg; adjusted β = 2.23, 95% CI: 1.92-2.54) compared to the control group. Nutritional improvements were consistent across subgroups, with no serious adverse events reported. Sensitivity analyses using categorical definitions of maternal nutritional status yielded results consistent with the primary analyses, confirming the robustness and public health relevance of the intervention effects. Daily consumption of amaranth grain flatbread significantly improved maternal anthropometric indicators, suggesting its potential as a sustainable nutritional intervention to enhance maternal nutritional status in resource-limited settings. These findings support integration of nutrient-rich traditional foods into maternal dietary programs.