Background: A recent epidemiological analysis on premenstrual dysphoric disorder (PMDD) in the community revealed increased rates of DSM-IV posttraumatic stress disorder (PTSD) among women suffering from PMDD. Aims: To explore whether this association is artifactual or might have important pathogenic implications. Methods: Data come from a prospective, longitudinal community survey of an original sample of N¼1488 women aged 14–24, who were followed-up over a period of 40 to 52 months. Diagnostic assessments are based on the Composite International Diagnostic Interview (CIDI) using the 12-month PMDD diagnostic module. Data were analyzed using logistic regressions (odds ratios) and a case-by-case review. Results: The age adjusted odds ratio between PTSD and threshold PMDD was 11.7 (3.0–46.2) at baseline. 10 women with full PTSD and at least subthreshold PMDD were identified at follow-up. Most reported an experience of abuse in childhood before the onset of PMDD. Some had experienced a life-threatening experience caused by physical attacks, or had witnessed traumatic events experienced by others. 3 women reported more than one traumatic event. Conclusions: A case-by-case review and logistic regression analyses suggest that women with traumatic events and PTSD have an increased risk for secondary PMDD. These observations call for more in-depth analyses in future research.