Author(s): Robson Marcelo Rossi | Valter Augusto della Rosa | Enrico Colosimo
Journal: Revista de Biologia e Ciências da Terra
ISSN 1519-5228
Volume: 3;
Issue: 1;
Date: 2003;
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Keywords: Ethnicity | age | Odds Ratio | sex
ABSTRACT
The influence of parents' age gap and their ethnicity in the determination of the sex of the first born child is provided. A descriptive analysis was undertaken and χ² test, association measures and logistic regression were applied to verify the relationship between variables. The chance that a male first child is born from a mother one to ten years older than the father is twice the chance of parents whose age gap ranges between 0 and 5 years, the father being the older. Further, the chance of a male first child born from an ethnically white male parent is approximately five times higher than that of an ethnically yellow one.
Journal: Revista de Biologia e Ciências da Terra
ISSN 1519-5228
Volume: 3;
Issue: 1;
Date: 2003;
VIEW PDF
DOWNLOAD PDF Original pageKeywords: Ethnicity | age | Odds Ratio | sex
ABSTRACT
The influence of parents' age gap and their ethnicity in the determination of the sex of the first born child is provided. A descriptive analysis was undertaken and χ² test, association measures and logistic regression were applied to verify the relationship between variables. The chance that a male first child is born from a mother one to ten years older than the father is twice the chance of parents whose age gap ranges between 0 and 5 years, the father being the older. Further, the chance of a male first child born from an ethnically white male parent is approximately five times higher than that of an ethnically yellow one.
