TY - JOUR T1 - JApan Y1 - 1929/06/15 N1 - 10.1001/jama.1929.02700500049022 JO - Journal of the American Medical Association SP - 2037 EP - 2037 VL - 92 IS - 24 N2 - Statistical Consideration of the First Menstruation of Japanese Women  Dr. J. Ishikawa, health officer of Kanagawa Prefecture, has published his statistical consideration of the first menstruation of Japanese women. He began to compile the statistics in June, 1928, aided by the local health officers of the country. He personally interviewed factory girls in some of the silk mills in his prefecture, as well as women in the Kanagawa branch of the Saiseikai Charity Hospital. The number of women amounted to 51,741. The investigation revealed that a great many Japanese women have their first menstrual discharge in the sixteenth year; the average age of the first discharge is 16, but any age between 13 and 19 seems to be within normal limits; there is a difference of age according to occupation—the first discharge of the geisha girls and other women of easy virtue comes earlier than that of the factory girls. SN - 0002-9955 M3 - doi: 10.1001/jama.1929.02700500049022 UR - http://dx.doi.org/10.1001/jama.1929.02700500049022 ER -