Regional and Racial Disparity of Preterm Birth Prevalence in Georgia, 1995–2012

Abstract

Preterm birth (PTB), defined as a live birth with a gestational age of less than 37 weeks, is the leading cause of infant mortality in developed countries. Recent studies have shown increases in PTB rates through the 1990s and 2000s in the United States, especially in a few states in the southeast including Georgia. Although researchers have studied the epidemiology of PTB in several regions, the spatial-temporal patterns of PTB rates in Georgia remain largely unexplored. This paper examines the spatial variations of PTB prevalence in Georgia at the county level between 1995 and 2012. Spatial clusters are assessed using global Moran's I and local indicators of spatial association (LISA). For disparity analysis, comparisons are made between births classified by race (black vs. white) and by four levels of urbanization. Results indicated a steady increase in PTB rates for both black and white births of all four urbanization classifications from 1995 to 2007, followed by a general decline from 2007 to 2012 for all groups. More urbanized counties tended to have lower PTB rates than more rural counties when compared as groups. Spatial clustering of high PTB rates tended to occur in the southern portion of the state for both white and black births, growing more prominent in the south central region as time progressed. Alternatively, spatial clustering of low PTB rates tended to occur in counties located in the north and northeastern areas of Georgia. The findings from this exploratory research are expected to serve as the basis of further studies of PTB and its risk factors, as well as to more effectively allocating prenatal health care resources.