RESUMO
1. The onset of menstruation, menstrual cycle, duration of the flow, and the influence of physical exercise in 464 women students coming from 46 provinces inthe Philippines were studied2. The onset of menstruation occurs most frequently between twelve and fourteen years of age, the greatest number falling at thirteen years of age3. The average duration of the menstrual flow is from three to five days, and the most common interval between menses in 28 days4. Physical exercise has a variable influence upon individuals, personal adaptation being the controlling factor5. The onset of menstruation seems to be the same in all girls in the Philippines irrespective of whether they have come from the north or south. However, definite conclusions cannot be made on this matter owing to the insufficiency of representative materials at hand. (Summary and conclusions)
