In an age when research is sweeping away many long-held medical misconceptions, the body of knowledge surrounding women's menstrual cycle remains tainted by age-old myths and taboos. These myths not only reflect inaccuracies, but also perpetuate "theories" about women's behavior that can be detrimental. It is not only in the personal realm, but in the political as well, that this issue gains importance. As long as policy-makers are influenced by suspicions about cyclic symptoms, women's emotional and intellectual stability will be questioned, with consequent repercussions in disability and employment practices. As nurses we have a vested interest in investigations that will establish a new data base from which to draw fresh insights, not only because it is relevant for female clients, but also because nursing as a profession is composed largely of women. As Wilma Scott Heide (1973) observes, "nursing suffers from the same oppression, prejudices, and limitations as women in our society." In other words, the problems of women are the problems of nursing.