Fertility preferences and intentions

Ideal and desired family size

In many societies, individuals and couples have ideas about how many children they want to have in their lives. Although responses may depend on questions, ideal family size reflects one's own ideal family size or targets and those regarded appropriate for the average or typical family size in a society (Morgan 2003). The ideal number of children provides a range within which socially acceptable or desirable fertility is defined. One's personal value, rather than perceived social value, of ideal number of children is frequently called desired family size.

Questions on ideal and desired family size often aims to collect numeric answers. But some couples may not have a fixed target, and may be more concerned about the timing of childbearing than the number. Non-numeric responses may be given by respondents, especially in pre-transitional and transitional populations. In the earlier rounds of Demographic Health Surveys (DHSs) in sub-Saharan Africa, a large minority of women provided non-numeric number, such as "don't know", "such things can't be known", "up to God" or "as many as God sends".

We often observe decline in desired family size during fertility transition. Generally, in societies in fertility transition total observed fertility often exceeds reported desired number of children. Conversely, ideal family size is often higher than total fertility rate in many low-fertility countries.

Questions

Ideal number of children can be asked both prospectively and retrospectively.

For example, Eurobarometer (EB) conducted in several European countries asked two questions:

  • "Generally speaking, what do you think the ideal number of children for a family?"
  • "And for you personally, what would be the ideal number of children you would like to have or would have liked to have had?"

Demographic and Health Surveys:

  •  "If you could go back to the time you did not have any children and could choose exactly the number of children to have in your whole life, how many would that be?"

Measures

Ideal and desired family size can be examined by various measures. Examples include:

  • Mean number of ideal/desired number of children
  • Proportions of women/men who want to specific number of children

The following indicator is constructed using the data on desired family size and will be introduced later in this session.

Limitations

Desired number of children is not regarded as a 'predictor' of fertility because it contains a strong element of idealisation and is influenced by social norms and mothers' rationalisations of their existing children, who may or may not have been desired at the time of conception (Westoff 1991).