A note on secular changes in the human sex ratio at birth.
نویسندگان
چکیده
Investigations of secular changes in the live-birth sex ratios of different countries have given conflicting results (Gini, 1908; Russell, 1936; Ciocco, 1938; Strandskov, 1942; Martin, 1943). In general the data are unsatisfactory, either because numbers of births are small, or because of inaccuracies and deficiencies in birth notification. Russell (1936) examined statistics for England and Wales, and drew attention to the decline of the sex ratio of live births between 1841-45 and 1896-1900, and to the sharp rise during and immediately after the 1914-18 war. Changes in the sex ratio of live births may be due to one or both of two causes:
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ورودعنوان ژورنال:
- British journal of social medicine
دوره 5 2 شماره
صفحات -
تاریخ انتشار 1951