Maternal health literacy as a potential determinant of infant and early childhood health: a systematic review

Background Maternal health literacy (MHL) represents a potentially modifiable public health determinant concentrated among socioeconomically disadvantaged populations. While 15–45% of pregnant women demonstrate inadequate health literacy, its impact across the full spectrum of infant and early childhood outcomes remains inadequately characterized, limiting understanding of its broader public health significance. Objective To systematically synthesize evidence on associations between MHL and infant/child health outcomes from birth through age three, and to examine whether MHL functions as a systemic determinant across outcome domains. Methods Following PRISMA guidelines, we searched MEDLINE, Embase, and Web of Science from inception through March 2025. Studies examining associations between validated MHL measures and any child health outcomes up to age three were included. Methodological quality was assessed using JBI checklists, and the certainty of evidence using the GRADE framework. Narrative synthesis was conducted. Results Eight studies ( n = 13,407 participants) from seven countries met inclusion criteria. Higher MHL was consistently associated with favorable birth weight. A pattern consistent with a behavioral pathway hypothesis emerged: outcomes requiring maternal behavioral competencies (e.g., symptom recognition, care-seeking) showed stronger and more consistent associations (e.g., reduced neonatal jaundice readmission, diaper dermatitis) than medically-determined conditions. Limited evidence also suggested MHL effects beyond the perinatal period, with inadequate MHL associated with increased risks of nutritional deficiencies and developmental delays (over four-fold increased risk in vulnerable populations). JBI assessment indicated generally adequate quality, while GRADE rated the certainty of evidence as Low to Very Low due to cross-sectional designs and imprecision. Conclusion MHL shows promising systematic associations with infant outcomes across multiple domains spanning the early life course, operating primarily through behavioral pathways requiring maternal agency. This pattern supports conceptualizing MHL as a potential foundational public health determinant and equity-relevant intervention target. However, low certainty of evidence underscores the need for standardized measurement, longitudinal studies, and intervention trials to establish causality.