In an effort to address important cross-cultural considerations in the study of posttraumatic stress disorder (PTSD), the present study is the first to assess the prevalence of a variety of potentially traumatic events among young Japanese women across life phases. Overall, our results proved similar to those reported in previous Western studies: Traumatic events were quite common among our participants (80.3%; n = 883). This finding is not surprising given that many of them lived through the 1995 Kobe earthquake. Yet our study found that even when “natural disaster'' was excluded, the rate remained 53.1%. Comparing four life phases, we found the most consistent differences between preschool and other life phases. The prevalence of potentially traumatic events and the percentage of most distressing events that participants reported were significantly lower in the preschool phase.