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

  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},
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.

An Environmental Cause Common to Sex Determination and Infant Mortality

There seems good evidence for Pongou’s (2013) proposal that male sex and infant mortality have a cause in common: high levels of maternal androgens, but it remains to be seen whether there are common sources of those androgens.

Gender Discrimination and Excess Female Under-5 Mortality in India: A New Perspective Using Mixed-Sex Twins

A sizable impact of explicit discrimination on girls’ excess mortality in India is documented, particularly compared with a placebo analysis in sub-Saharan Africa, where girls have a survival advantage.

Gender Differences in Infant Mortality and Neonatal Morbidity in Mixed-Gender Twins

The results of the study indicated that in mixed-gender twin pairs, the odds of infant mortality and neonatal morbidity were higher in male twins than their female co-twins.

Droughts and Gender Bias in Infant Mortality in Sub-Saharan Africa

Are African girls more exposed than boys to risk of infant mortality during crises and if so, is the difference due to discrimination? To answer these questions, we combine retrospective fertility

Mortality convergence of twins and singletons in sub-Saharan Africa

BACKGROUND While there is a substantial amount of literature documenting that twins have higher mortality than singletons, that literature does not address the questions of whether this disadvantage

The Differential Mortality of Undesired Infants in Sub-Saharan Africa

Undesired gender composition is more important for infant mortality than undesired childbearing and may also lead couples to increase family size beyond the maternal desire, in which case infants of the surplus gender are particularly vulnerable.

The large contribution of twins to neonatal and post-neonatal mortality in The Gambia, a 5-year prospective study

Mortality among twins makes a significant contribution to the high burden of neonatal and post-neonatal mortality in The Gambia and preventive interventions targeting twins should be prioritized.

Are human natal sex ratio differences across the world adaptive? A test of Fisher's principle

This work shows how the failure to account for residual spatial autocorrelation in the residuals can lead to incorrect conclusions regarding support for predictions from sex allocation theory.

The sex gap in neonatal mortality and the AIDS epidemic in sub-Saharan Africa

Trends in the sex gap in neonatal death—death occurring within 1 month of birth-during the era of the AIDS epidemic are analyzed, and it is argued that they were sensitive to the availability of antiretroviral medicines.



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