Overview

Objectives
The project aimed to investigate the determinants of fertility postponement, to identify the impact of postponement on subsequent childbearing and to understand the factors facilitating fertility recuperation (catching up) at older age. Given the decline in the probability that conception will occur among women in their thirties and the upper age at which women are physically able to have children, many of those who are childless at age 30 do not manage to 'catch up' their childbearing. Indeed England and Wales has one of the highest levels of childlessness in Europe with about one in five women reaching age 45 with no children.

Methods
The project involved a data preparation phase and an analysis phase. In order to examine childbearing trends in the context of the cohort members' other life course domains, the retrospective fertility, partnership, education and employment histories needed to be cleaned, seamed and integrated. Working in conjunction with members of Centre for Longitudinal Studies Institute of Education, the task was completed for both cohorts in men and women. The analysis was divided into 3 parts: the 1958 cohort; the 1970 cohort; and a cross-cohort comparison. Work on the 1958 cohort, looked at how parental background and experiences in childhood and early adulthood influence the early development, and modifications of family building intentions. Study of the 1970 cohort, now reaching the end of their reproductive years, examined the role of men's and women's relative resources in facilitating recuperation between age 30 and 38. And the cross-cohort comparison looked at the impact of education, employment and partnership experiences on the recuperation of fertility at older ages.

Findings
By taking a life course approach the research shows how fertility intentions and behaviour develop from adolescence, through early adulthood and into mid-life. The 1958 and 1970 cohort datasets provided a unique opportunity to understand how fertility intentions in early adulthood are changed by later life experiences, particularly partnership formation and dissolution, economic uncertainty (especially for men), and commitment to full time work (especially for women).

Parental and childhood experiences are particularly good at predicting who becomes a parent in their teens or early twenties, but are less useful for predicting who becomes a parent among those still childless in their early thirties. Among this group, more educated men and women intend to have children and are more likely to have a child.

Fertility intentions predict fertility outcomes – and the effect size is second only to partnership status. However, positive intentions expressed at age 30 remained unfulfilled for around four in ten men and women suggesting that there remain significant barriers to recuperation, most obviously the lack of a co-residential partner. A significant proportion (ranging between one quarter and one third) of the childless men and women in their early thirties were uncertain about their future childbearing. Uncertainty among men is similar across educational groups but this is not the case for women where it is those with degree level qualifications who appear most uncertain. This may reflect the greater opportunity costs of childbearing for such women. Uncertainty is particularly high for women who were high earners, but whose partners were in the low earners. Recuperation was strongest among couples where both are high earners.