Past research provides evidence for trajectories of health and wellness among individuals following disasters that follow specific pathways of resilience, resistance, recovery, or continued dysfunction. These individual responses are influenced by event type and pre-event capacities. This study was designed to utilize the trajectories of health model to determine if it translates to population health. We identified terrorist attacks that could potentially impact population health rather than only selected individuals within the areas of the attacks. We chose to examine a time series of population birth outcomes before and after the terrorist events of the New York City (NYC) World Trade Center (WTC) attacks of 2001 and the Madrid, Spain train bombings of 2004 to determine if the events affected maternal-child health of those cities and, if so, for how long. For percentages of low birth weight (LBW) and preterm births, we found no significant effects from the WTC attacks in NYC and transient but significant effects on rates of LBW and preterm births following the bombings in Madrid. We did find a significant positive and sustained effect on infant mortality rate in NYC following the WTC attacks but no similar effect in Madrid. There were no effects on any of the indicator variables in the comparison regions of New York state and the remainder of Spain. Thus, population maternal-health in New York and Madrid showed unique adverse effects after the terrorist attacks in those cities. Short-term effects on LBW and preterm birth rates in Madrid and long-term effects on infant mortality rates in NYC were found when quarterly data were analyzed from 1990 through 2008/2009. These findings raise questions about chronic changes in the population's quality of life following catastrophic terrorist attacks. Public health should be monitored and interventions designed to address chronic stress, environmental, and socioeconomic threats beyond the acute aftermath of events.