RT Journal
T1 JApan
JF Journal of the American Medical Association
JO Journal of the American Medical Association
YR 1929
FD June 15
VO 92
IS 24
SP 2037
OP 2037
DO 10.1001/jama.1929.02700500049022
UL http://dx.doi.org/10.1001/jama.1929.02700500049022
AB 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.