Son-biased sex ratios in the 2000 United States Census
- Douglas Almond * , † and
- Lena Edlund * , ‡
- *Department of Economics, Columbia University, New York, NY 10025; and
- †National Bureau of Economic Research, 1050 Massachusetts Avenue, Cambridge, MA 02138
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Edited by Ronald Lee, University of California, Berkeley, CA, and approved March 3, 2008 (received for review January 24, 2008)
Abstract
We document male-biased sex ratios among U.S.-born children of Chinese, Korean, and Asian Indian parents in the 2000 U.S. Census. This male bias is particularly evident for third children: If there was no previous son, sons outnumbered daughters by 50%. By contrast, the sex ratios of eldest and younger children with an older brother were both within the range of the biologically normal, as were White offspring sex ratios (irrespective of the elder siblings' sex). We interpret the found deviation in favor of sons to be evidence of sex selection, most likely at the prenatal stage.
Footnotes
- ‡To whom correspondence should be addressed. E-mail: le93{at}columbia.edu
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Author contributions: D.A. and L.E. designed research, performed research, contributed new reagents/analytic tools, analyzed data, and wrote the paper.
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The authors declare no conflict of interest.
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This article is a PNAS Direct Submission.
- © 2008 by The National Academy of Sciences of the USA
