BACKGROUND: Relationships between maternal preconception health and preterm birth have been demonstrated in the literature, as have relationships between neighborhood factors and maternal preconception health. Determining how maternal preconception health and neighborhood factors simultaneously contribute to preterm birth will help researchers and clinicians better understand the complex risk factors of preterm birth.

METHODS: Data were collected during 2012-2014 in the Georgia Pregnancy Risk Assessment Monitoring System. Data were geocoded to American Community Survey 2011-2015 5-year estimates (n=3085). Descriptive statistics were calculated. Effects of maternal preconception health and neighborhood factors on preterm birth were analyzed using hierarchical generalized linear modeling (SAS PROC GLIMMIX).

RESULTS: From 2012-2014, about 9.38% of Georgia moms gave birth to a preterm infant. Considering cross-level interactions, for women who reported recently dieting and who lived in census tracts with 1.00% more crowded households than average, the estimated odds of preterm birth were 0.83 times the estimated odds for the average interaction (95% CI 0.81-0.85). For women with a pre-pregnancy chronic disease who lived in rural counties, the estimated odds of preterm birth were 1.35 times the estimated odds for the average interaction (95% CI 1.17-1.57).

CONCLUSIONS: Maternal preconception health and neighborhood factors were simultaneously significantly associated with preterm birth, demonstrating the complexity of risk factors associated with preterm birth. Programs to promote healthy weight management and exercise before pregnancy and to encourage physicians to work in rural counties could improve maternal preconception health and decrease preterm births.