The cause and control of sex in human offspring.

  • Jackson, R. Clay.
Date:
1926
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: The cause and control of sex in human offspring. Source: Wellcome Collection.

    117/222 (page 113)
    The Cause and Control of Sex 113 ever been discovered or adduced. (Par. 139.) The first one, the observation by Dr. Romme, was mentioned. In the bulletin by Professor Newcomb the other two come to light. One is in setting up the proposition that very young parents tend to produce an abnormal pro¬ portion of male children. Vienna statistics are cited as showing 13% excess of boys born to fathers under twenty-five years of age. For mothers under seventeen years of age there is an excess of boys born to the extent of 171%, (a male sex ratio of 2.71). For Nor¬ way, to fathers below twenty years, the excess of boys born is 17%. And for the young parents of the United States, among all the first born children, boys are in the majority by 19%. The total effect of all statistics cited in the bulletin is so disconcerting to Professor Newcomb, that he thinks there has been negligence in the reporting of female births. He attempts to dis¬ credit the figures and complains that in the item of young Austrian mothers, (an excess of 171% male births), the total number of cases reported, 26, is too small to warrant any conclusions. This may be true, but it should have stimulated him to go out with note¬ book and pencil and secure a sufficient quota of such cases. 208. During one period of a few weeks in Detroit, Michigan, I canvassed 187 cases of mothers with their first born. None of these mothers was more than twenty-two years of age, apparently, and in every case the infant was too young to decide its sex independent of inquiry. Of these 187 births there were 56 girls and 131 boys, a male sex ratio of 2.34 ; not far from Pro¬ fessor Newcomb's citation on Vienna. One will readily agree that 187 cases, taken at random, would be a fair quota, hence it is certain that for very young mothers, or among first born children there is an excessively high male sex ratio. This I consider to be the second fact of importance for the human species. 209. In the first place I noticed in the 187 cases just referred to, that these young mothers were almost