The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) established the Nulliparous Research Network to study women for whom the current pregnancy will lead to their first delivery (nulliparas). In this study the Network enrolled a cohort of a racially/ethnically/geographically diverse population of 10,000 nulliparous women to undergo intensive research assessments during the course of their pregnancies to study the prediction and prevention of adverse pregnancy outcomes such as preterm birth, preeclampsia, fetal growth restriction, and stillbirth. RTI has served as the Data Coordinating and Analysis Center (DCAC) for the project and has established a scientific partnership with Steering Committee membership to transform the research agenda into operationally sound protocols, developed study materials, developed and implemented data collection and management systems at the DCAC and the clinical sites, provided quality assurance for Network operations, and developed procedures for and conducted data analysis. The information gained from the Nulliparous Research Network will benefit women who are pregnant or who are considering pregnancy and their physicians. In addition, the knowledge will support future research aimed at improving a critical group of at-risk women who are currently understudied.