Effect of the menstrual cycle on the stability of the task performance in the monotonous work

In Japan, the number of female workers has been increasing. But now, the trade is dull and employment opportunities for women have become narrow. One of the reasons, perhaps, is the misunderstanding for women: the quality of their tasks is unstable. The aim of this study is to research on a construction of an Amenity and Safety Management system for female workers. From this point of view, the authors have performed an experiment by measuring the number of the tasks and so on by using personal computer. The authors´ results confirmed that in some of females there were quantitative relations between menstrual phases and stability of the monotonous task efficiency. In the low body temperature phase, there were females whose variation over each 5 minutes was less than other phases. And their degree of variation by the phase difference was larger than those of the others