Why Is Infant Mortality Higher in Boys Than in Girls? A New Hypothesis Based on Preconception Environment and Evidence From a Large Sample of Twins

@article{Pongou2012WhyII,
  title={Why Is Infant Mortality Higher in Boys Than in Girls? A New Hypothesis Based on Preconception Environment and Evidence From a Large Sample of Twins},
  author={Roland Pongou},
  journal={Demography},
  year={2012},
  volume={50},
  pages={421-444}
}
Infant mortality is higher in boys than girls in most parts of the world. [] Key Result Using a large sample of twins from sub-Saharan Africa, I find that both preconception environment and child biology increase the mortality of male infants, but the effect of biology is substantially smaller than the literature suggests. I also estimate the interacting effects of biology with some intrauterine and external environmental factors, including birth order within a twin pair, social status, and climate.

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...

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