Background Prevalence of premenstrual syndrome (PMS) may be as high as 13-18%, but it remains under-recognized and is associated with increased suicidal ideation (SI), plans, and attempts in epidemiological studies. The present study reports on women endorsing premenstrual SI (PMSI) and characterizes this at-risk group and its clinical correlates. Methods A cross-sectional study assessed demographics, anxiety and depression severity, psychiatric diagnoses, menstrual symptoms, SI, and trauma in adult women at a major medical center over 11 months. Results Three hundred two women were assessed. Of 153 participants endorsing premenstrual symptoms, 41 (27%) reported new or worsening concurrent premenstrual passive or active SI. Women who reported PMSI were significantly more likely to be single, unemployed, and childless as well as significantly more likely to report interference from premenstrual symptoms, histories of psychiatric hospitalization, adverse childhood events, suicide attempts, and current and past depression and anxiety compared to women without PMSI. The final regression model indicated the most significant predictors of PMSI were history of a depression diagnosis, severity of current depressive symptoms, and having experienced 3 or more childhood adverse events. Conclusion Nearly one-third of women reporting premenstrual symptoms endorsed concurrent SI, a clinically valuable demonstration of the importance of this predictable cyclic risk factor.