Analyzing the Human Sex Ratio at Birth

Abstract

The effect of income, education, employment, marital status, age, race, birth order, and national economic conditions on the sex ratio at birth were analyzed for the N = 21,597 children of the National Longitudinal Survey of Youth 1979 participants. These data were analyzed for individual births using a logistic regression model, treating the sex of each child as the outcome variable, and were analyzed for families using a linear regression model, treating the proportion of male children in each family as the outcome variable. No variable was statistically significantly related to the sex ratio. These findings suggest that the sex ratio at birth may not be affected by the individual- and population-level factors commonly examined in past research.