Figure 2From: Area-level risk factors for adverse birth outcomes: trends in urban and rural settings B- Splines Representing Long-Term Alabama Adverse Birth Outcome Trends for (A) PTB by Rural– urban Commuting Area Code category (B) PTB by Population Density Tertile (C) LBW by Rural–urban Commuting Area Code category and (D) LBW by Population Density Tertile. Back to article page