The research on the relationship between suicidal behavior & the phases of the menstrual cycle is reviewed. Results for numerous studies on attempted & completed suicide & menstruation are detailed. Possible explanations are provided, e.g. the change in levels of circulating estrogen & progesterone during the bleeding phase of the menstrual cycle may affect the timing of attempts. Study results on suicidal behaviors among pregnant women & women taking birth control pills are also provided. (VM)