HJAR May/Jun 2025

Specifically, we included maternal age (<20, 20–29, 30–39, ≥40 years); education (ele- mentary [less than high school], secondary [graduated from high school], some college or higher); and live birth order (1, 2, or ≥ 3). 2.3. Statistical analyses Summary statistics were computed for all study variables. Rates were calculated per 10,000 live births for the four study out- comes (i.e., total number of reported pre- natal care visits, reporting fewer than the recommended number of prenatal care vis- its, reporting late initiation of prenatal care, and reporting no prenatal care). Adjusted rates ratios (ARRs) were calculated using estimated marginal means frommultivari- able modified Poisson regression models adjusting for maternal age, maternal educa- tion, and parity with a three-way interaction for payer, race/ethnicity, and rural/urban residence. The interaction was included because of the possible effects of intercon- nection of these variables (e.g., the effect of rural/urban residence may be moderated by race and/or payer). Additionally, gestational age was also included as a covariate in the number of prenatal care visits model since those with a higher gestational age would have greater opportunity for more prenatal care visits. We used the “emmeans”R pack- age with CIs calculated using an asymptotic method with a multivariate-t adjustment for multiple comparisons (Searle et al., 1980). Statistical significance was assumed at p < 0.05. All statistical analyses were performed using R version 4.3.2. 3. RESULTS 3.1. Descriptive statistics We identified 333,460 singleton live births in Arkansas, of whom 298,055 indi- catedMedicaid or private insurance (includ- ing TRICARE and IHS) as the primary payer. Characteristics of the study population can be seen in Table 1. Among the sample, the average number of reported prenatal care visits was 10 (SD = 4), 43.0 % reported fewer than the recommended number of prena- tal care visits, 29.0 % reported late initia- tion of prenatal care, and 2.3 % reported no PRENATAL CARE 12 MAY / JUN 2025 I  HEALTHCARE JOURNAL OF ARKANSAS