Age at menarche in South African Bantu schoolgirls living in the Transkei Reserve.
1961; National Institutes of Health; Volume: 33; Linguagem: Inglês
Autores
R. J. W. Burrell, M. J. R. Healy, J. M. Tanner,
Tópico(s)Growth Hormone and Insulin-like Growth Factors
ResumoTHE age at which the first menstrual period, or menarche, occurs is a measure much used by students of growth and development in assessing the speed of maturation of individuals, or, on a group basis, of populations. It is known to be influenced by both hereditary and environmental factors. State of nutrition is the most important environmental factor; climate was formerly thought to exert some effect, but modern data make it clear that its influence, if any, is very limited. Within a relatively homogeneous culture such as that represented by the South of England or by Denmark, the children of the top socioeconomic groups reach menarche two or three months earlier than children of the lowest socio-economic groups. There is some evidence of racial differences, or differences associated with national origin, but the over-riding effects of nutrition have obscured any certain knowledge of these. Currently the average age of menarche in school children in London and the South of England is 13.1 years; the average for a wellnourished, well-circumstanced group of Burmese and Assamese has been reported as 13.2 years (for bibliography see Tanner, 1961). In these circumstances extensive data from different population groups, and particularly non-European ones, are to be welcomed, and this paper reports statistics for a sample of 47,420 South African Bantu girls living in the Transkei reserve and divided into two groups on a socio-economic basis. The paper is of additional interest, we hope, in that for the first time a test of the logistic distribution, as well as the more commonly used normal distribution, has been made for fitting the proportions of girls having menstruated at each month of age. It
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