Undernutrition in Infants Aged Under Six Months: A Multi-Center Cross-Sectional Study in Two Governorates in Yemen

Background/Objectives: Data on undernutrition among infants under six months (<6 m) in Yemen are limited. This study aimed to estimate the prevalence of conventional, concurrent and severe forms of anthropometric failure among infants < 6 m attending routine health visits in two Yemeni governorates and to determine the anthropometric indicator that shows greater overlap with these failures. Methods: This facility-based survey was conducted over thirteen months in five health facilities. We measured infants’ weight, length and mid-upper arm circumference (MUAC). Weight-for-age (WAZ), length-for-age (LAZ), and weight-for-length z-scores (WLZ), composite index of anthropometric failure (CIAF), and composite index of severe anthropometric failure (CISAF) were calculated. Additionally, we assessed the overlap of different MUAC thresholds and WAZ < −2 with various forms of anthropometric failure. Results: In total, 5053 infants were analyzed. Further, 19.3% (95% CI: 15.1; 24.3), 17.7% (95% CI: 13.8; 22.5), and 30.5% (95% CI: 21.8; 40.7) were wasted, stunted and underweight, respectively. Overall, 40.9% (95% CI: 34.7; 47.5) were classified as (CIAF). Within the CIAF group, 17.7% (95% CI: 12.5; 24.4) had a single anthropometric failure and 23.3% (95% CI: 17.9; 29.7) had concurrent failures. Furthermore, 12% (95% CI: 10.8; 13.4) of all infants exhibited the most severe forms of anthropometric failure (CISAF). WAZ < −2 overlapped with a significantly higher proportion of infants with anthropometric failure compared to MUAC: CIAF (74.4% vs. 28.8%) and CISAF (92.1% vs. 47%). Conclusions: Conventional, concurrent and severe anthropometric failures are common among <6 m infants in Yemen. WAZ captured more at-risk infants than MUAC.