Association of Health Literacy Among Nulliparous Individuals and Maternal and Neonatal Outcomes.

Importance: Health literacy is considered an important social determinant of health that may underlie many health disparities, but it is unclear whether inadequate health literacy among pregnant individuals is associated with adverse maternal and neonatal outcomes. Objective: To assess the association between maternal health literacy and maternal and neonatal outcomes among nulliparous individuals. Design, Setting, and Participants: This was a secondary analysis of a large, multicenter cohort study of 10 038 nulliparous individuals in the US (2010-2013). Participants underwent 3 antenatal study visits and had detailed maternal and neonatal data abstracted. Data analysis was performed from July to December 2019. Exposures: Between 16 and 21 weeks of gestation, health literacy was assessed using the Rapid Estimate of Adult Literacy in Medicine-Short Form, a validated 7-item word recognition test. In accordance with standard scoring, results were dichotomized as inadequate vs adequate health literacy. Main Outcomes and Measures: On the basis of theoretical causal pathways between health literacy and health outcomes, a priori maternal and neonatal outcomes (determined via medical records) were selected for this analysis. Multivariable Poisson regression models were constructed to estimate the associations between health literacy and outcomes. Sensitivity analyses in which education was removed from models and that excluded individuals who spoke English as a second language were performed. Results: Of 9341 participants who completed the Rapid Estimate of Adult Literacy in Medicine-Short Form, the mean (SD) age was 27.0 (5.6) years, and 2540 (27.4%) had publicly funded prenatal care. Overall, 1638 participants (17.5%) had scores indicative of inadequate health literacy. Participants with inadequate health literacy were more likely to be younger (mean [SD] age, 22.9 [5.0] vs 27.9 [5.3] years), have less educational attainment (some college education or greater, 1149 participants [73.9%] vs 5279 participants [94.5%]), have publicly funded insurance (1008 participants [62.2%] vs 1532 participants [20.0%]), and report they were a member of an underrepresented racial or ethnic group (non-Hispanic Black, 506 participants [30.9%] vs 780 participants [10.1%]; Hispanic, 516 participants [31.5%] vs 948 participants [12.3%]) compared with those with adequate health literacy. Participants who had inadequate health literacy had greater risk of cesarean delivery (adjusted risk ratio [aRR], 1.11; 95% CI, 1.01-1.23) and major perineal laceration (aRR, 1.44; 95% CI, 1.03-2.01). The adjusted risks of small-for-gestational-age status (aRR, 1.34; 95% CI, 1.14-1.58), low birth weight (aRR, 1.33; 95% CI, 1.07-1.65), and 5-minute Apgar score less than 4 (aRR, 2.78; 95% CI, 1.16-6.65) were greater for neonates born to participants with inadequate health literacy. Sensitivity analyses confirmed these findings. Conclusions and Relevance: These findings suggest that inadequate maternal health literacy is associated with a variety of adverse maternal and neonatal outcomes.