For many parents, labor, delivery, and/or the perinatal and neonatal periods present significant stressors that result in clinically significant parental feelings of psychological distress or trauma. This review article identifies known preexisting risk, and protective, factors for such distress, focusing on individual variables and familial or other social support networks. Research describing the full range of possible psychological reactions is also presented, loosely categorized as representing psychological outcomes of resiliency or growth, externalized distress, and internalized distress. These outcomes are viewed as neither linear nor mutually exclusive, and specific implications for each outcome are presented. The primary focus of this review is on the most well understood internalizing distress outcome during the perinatal period, maternal posttraumatic stress reactions. The utility of a brief, freely available measure quantifying such distress is also overviewed, including standards for its usage. Healthcare and particularly nursing staff are encouraged to attend to the range of possible psychological outcomes that may emerge during the perinatal period, identifying distressed mothers, so that they may be referred for care. The review concludes by presenting recommended future directions for research regarding the measurement of posttraumatic stress disorder in parents.