Community and individual level factors influencing preterm birth: A multilevel analysis

Background: Reducing rates of adverse birth outcomes for all mothers is a central focus of public health efforts. Multilevel studies examining adverse birth outcomes have focused on infant mortality and low birth weight. Considering preterm birth is one of the main contributing factors to infant mortality and low birth weight, multilevel factors associated with preterm births should be investigated. The objective of this study is to determine individual-level and community-level factors predicting the rate of preterm birth.

Methods: This study was conducted using vital birth record data for Richmond City, Virginia, violence related ambulance pick up data and population level data obtained from the U.S. Census. Logistic regression was conducted to identify the best predictive model and a combined or hierarchical model was examined using all variables from both levels.

Results: There were 30,591 live births that occurred in Richmond, Virginia between 1997 and 2007. Preterm births occurred in 12.3 per 100 births in this study. Maternal age, race, education, paternal presence, and adequacy of prenatal care, as well as percent black and percent poverty in the block group were significant predictors of preterm birth. Violence related ambulance pick up was not significantly associated with preterm birth.

Conclusions: These results demonstrate the use of multilevel modeling in identifying significant individual and community level factors that are associated with preterm birth. The findings of this study identified modifiable environmental and individual risk factors for future interventions.