Association between anemia in pregnant adolescents and neonatal birth weight in a secondary-level hospital in Mexico.

Abstract

Introduction: Anemia during pregnancy is a risk factor for adverse perinatal outcomes, especially among adolescents, a group facing greater biological and social vulnerabilities. This study aimed to assess the association between third-trimester maternal anemia and neonatal birth weight in a sample of pregnant adolescents in Mexico. Method: A cross-sectional, retrospective, and analytical study was conducted through a review of clinical records from a secondary-level public hospital in Culiacán, Sinaloa. Adolescents (≤19 years) with full-term deliveries between January and April 2023 were included. Anemia was defined as hemoglobin <11 g/dL. Neonatal outcomes were compared between mothers with and without anemia, and the relationship between maternal hemoglobin and birth weight was analyzed. Results: A total of 276 pregnant adolescents were analyzed. The prevalence of anemia was 28.98%. The mean birth weight was significantly lower in neonates born to mothers with anemia compared to those without (3,254 g vs. 3,353 g; p = 0.0397), although no association was found with low birth weight (<2,500 g; p > 0.05). No significant correlation was found between maternal hemoglobin levels and neonatal weight. Adolescents aged 13–16 years had a higher risk of anemia compared to those aged 17–19 years (OR: 3.234; p < 0.001). Conclusion: Anemia in pregnant adolescents was associated with a significant reduction in mean neonatal birth weight, without increasing the proportion of low birth weight. These findings highlight the need to strengthen screening and timely treatment of anemia during adolescent pregnancy to prevent adverse neonatal outcomes.