Transgenerational effects of posttraumatic stress disorder in babies of mothers exposed to the World Trade Center attacks during pregnancy.

CONTEXT Reduced cortisol levels have been linked with vulnerability to posttraumatic stress disorder (PTSD) and the risk factor of parental PTSD in adult offspring of Holocaust survivors. OBJECTIVE The purpose of this study was to report on the relationship between maternal PTSD symptoms and salivary cortisol levels in infants of mothers directly exposed to the World Trade Center collapse on September 11, 2001 during pregnancy. DESIGN Mothers (n = 38) collected salivary cortisol samples from themselves and their 1-yr-old babies at awakening and at bedtime. RESULTS Lower cortisol levels were observed in both mothers (F = 5.15, df = 1, 34; P = 0.030) and babies of mothers (F = 8.0, df = 1, 29; P = 0.008) who developed PTSD in response to September 11 compared with mothers who did not develop PTSD and their babies. Lower cortisol levels were most apparent in babies born to mothers with PTSD exposed in their third trimesters. CONCLUSIONS The data suggest that effects of maternal PTSD related to cortisol can be observed very early in the life of the offspring and underscore the relevance of in utero contributors to putative biological risk for PTSD.