The present study investigated prenatal and early postnatal risk factors associated with developmental patterns of disruptive behaviors (DBs; e.g., hyperactivity-impulsivity, noncompliance, physical aggression) from ages 1.5 to 5 years in a population birth cohort (N = 2,057; 50.7% boys). Six high-trajectory classes obtained by latent growth modeling were used as longitudinal indicators of single-DB and co-occurrent DBs. Children following low or moderate trajectories for all DBs served as the reference class. Results showed low commonality of risk factors among single-DB trajectory classes, suggesting that "pure" forms of DBs have specific etiologies. In contrast, the trajectory classes with a high DB in common shared 20.0% to 46.7% of their risk factors. Overall, 40.0% of significant risk factors across trajectory classes were common to between two and four classes, whereas 60.0% of the significant risk factors were specific to one class or another. However, risk factors common among classes accounted for the greater part (63.2%) of the associations, especially in co-occurrent DBs trajectory classes. These risk factors included male sex, a higher number of siblings, maternal symptoms of depression and conduct problems, young motherhood, lack of positive parenting, family dysfunction, and lower socioeconomic status. Children thus develop early distinct patterns of DBs associated with both common and specific prenatal and early postnatal risk factors. Longitudinal assessments of early manifestations of DB, including a range of behaviors and a variety of potential risk factors to reflect the distinctiveness of children and their families, could help guide etiological research, tailor early interventions, and prevent a cascade of deleterious influences and outcomes.