Male preference and family size.

The influence on family size of the sex of the first children was studied in a sample of 1851 families of students in Sevilla University. Significantly more families limited family size to two or three children when the two or three children were of the same sex than in the opposite case. Significantly more families limited family size to three children when not all the three first children were females. The frequency of families having more than three children is not increased to a larger extent when the three first children are males than in the other cases.