Fifty-six mothers of premature infants who participated in a study to reduce symptoms of posttraumatic stress disorder (PTSD) completed the Brief COPE, a self-report inventory of coping mechanisms, the Stanford Acute Stress Reaction Questionnaire to assess acute stress disorder (ASD) and the Davidson Trauma Scale to assess PTSD. 18 % of mothers had baseline ASD while 30 % of mothers met the criteria for PTSD at the 1-month follow-up. Dysfunctional coping as measured by the Brief COPE was positively associated with elevated risk of PTSD in these mothers (RR = 1.09, 95 % CI 1.02-1.15; p = .008). Maternal education was positively associated with PTSD; each year increase in education was associated with a 17 % increase in the relative risk of PTSD at 1 month follow-up (RR = 1.17, 95 % CI 1.02-1.35; p = .03). Results suggest that dysfunctional coping is an important issue to consider in the development of PTSD in parents of premature infants.