According to the 1990 census, 84% of households were headed by males. Nonetheless, the sustenance and reproduction of the family are responsibilities of several family members, especially women. The number of single-woman headed households rose notably from 1970 to 1990, especially in urban areas.

Average fertility is three children per woman, and dwellings house an average of 5.1 persons each.12 Due to the large number of young women who have yet to attain the total number of live births, percentage data on fertility are distorted. In rural areas dwellings are occupied by extended families. This trend is less common in urban areas.

In Oaxaca young girls assume responsibilities in the home from a young age (7 years at the latest). They become involved in domestic chores such as caring for their siblings and the yard animals. From 15 years, young women are considered suited for marriage 39% marry when they are 15- to 19-years-old. The percentage of women separated, divorced, or widowed is greater than men in all age groups. It is more common for men to marry again, which contributes to the large number of single mothers under 20.

Boys go to school longer, on average, than girls. Even so, they too participate in work from a young age, mainly helping their fathers in the fields. When marrying (40% marry at 22 to 24 years, 16.4% at 15 to 19 years), young men become involved in the civic life of the community, providing services such as topil (community policing) or taking responsibility for more important tasks.

There is no quantitative or qualitative data on the consequences of migration on the family group. Even so, it is known that migration is a factor of instability in the family life of Oaxacans. This is reflected in different types of family disintegration. In some cases only the father migrates, on a temporary basis, and the children stay with the mother. Less commonly, the children stay with a relative or accompany their parents. Many children of migrants abandon their home and seek work in the cities of Oaxaca because they have been left behind.