Factors Associated with Anemia in Pregnant Women: A Narrative Review Factors Associated with Anemia in Pregnant Women: A Narrative Review

ปัจจัยที่สัมพันธ์กับภาวะโลหิตจางในหญิงตั้งครรภ์: การทบทวนวรรณกรรม

Abstract

Anemia in pregnancy is an important health problem with multifactorial determinants and potential adverse effects on maternal and fetal health. This narrative review aimed to review and synthesize evidence on factors associated with anemia among pregnant women. The PEO framework was used to define the review question and scope. Studies published from January 1, 2021, to December 31, 2025, were searched in PubMed, Scopus, CINAHL, ScienceDirect, the Cochrane Library, Google Scholar, and ThaiJO. A total of 1,620 records were identified. After duplicate removal, title and abstract screening, and full-text eligibility assessment, 12 studies were included in the narrative synthesis. Study selection, data extraction, and quality appraisal were independently conducted by two reviewers, with disagreements resolved through discussion and consensus. Analytical cross-sectional studies were appraised using the JBI Critical Appraisal Checklist for Analytical Cross-Sectional Studies, whereas the longitudinal study was appraised using the JBI Critical Appraisal Checklist for Cohort Studies. Data were analyzed using narrative synthesis combined with thematic analysis. Five groups of associated factors were identified: nutritional and health behavioral factors; obstetric and reproductive factors; socioeconomic factors; healthcare access factors; and infection and health-related factors. Factors most frequently reported with relatively consistent directions of association included non-receipt or irregular use of iron–folic acid supplementation, short interpregnancy interval, third-trimester pregnancy, bleeding during pregnancy, and inadequate or low-diversity dietary intake. Low income, rural residence, limited knowledge, inadequate antenatal care follow-up, malnutrition, malaria, and hookworm infection were also reported, although the consistency and applicability of these findings varied across settings. Most included studies were cross-sectional; therefore, the findings indicate associations rather than causal relationships. Antenatal care services should adopt comprehensive risk assessment, monitor hemoglobin levels and adherence to iron supplementation, assess nutritional and socioeconomic barriers, and investigate alternative causes of anemia when treatment response is inadequate.