The burden of perinatal morbidity and mortality related to preterm birth (PTB) is astounding. Studies show that environmental exposures contribute to an increased susceptibility to PTB. Identification of the causative etiology of PTB is essential to improving global maternal and child health. Our preliminary data reveal that exposure to polycyclic aromatic hydrocarbons (PAHs) is associated with PTB. We have reported that proximity to Superfund sites in Harris County is associated with very low birth weight, and our studies reveal higher levels of PAHs in placentas from PTBs compared to term births specifically in women residing near Superfund sites. In this proposal we will delve into the molecular underpinnings behind PTB and the specific environmental exposures of PAHs through use of our established transcriptomic and epigenomic pipelines. We will leverage our readily available serum and placental samples from a population based and PTB enriched cohort. Furthermore, geostatistical modeling will be utilized to identify clusters of PTB throughout Harris County. Our central hypothesis underlying our research is that PAH exposures are associated with an increased rate of PTB, that transcriptomics and epigenomics will yield readily translatable mechanistic information on this association, and geostatistical modeling will reveal increased clusters of PTB in proximity to Superfund sites in Harris County.