Deciding to have a baby is an easier step for public sector workers

'The results show that the decision to have a child is often far from straightforward, especially for women. There is a strong link between women's employment and fertility but not between men's work and fertility. 'Women's decisions about both work and having children seem to be linked to values, beliefs and other characteristics which are not measured in surveys, whereas men have children regardless of their orientation towards work,' says Dr Nazio.

'However, we did find a strong link between the pattern of men's careers and women's and it is also clear that children are more likely to be born in situations where it is easier for women to move in and out of the labour market, or to reduce their working hours for a period.'

Contrary to expectations, the research revealed that temporary employment contracts, which are increasingly common for both men and women, do not put couples off parenthood. 'Part-time employment, on the other hand, has a positive effect on childbirth, which may have been a key factor in sustaining British fertility,' Dr Nazio says.

The study also reveals that the effect of redundancy on household working patterns is polarised. In some cases, where a man repeatedly loses his job, his wife quits hers as well. In other cases, the wife goes back to work to shield the family from falling into poverty.

'The behaviour is related to household type. Women with more qualifications may find it easier to find work, but those in low-paid jobs may be financially better off not working if their partner loses his job,' Dr Nazio says.

'Understanding the behaviour of households, as well as individuals, is particularly important because spouses increasingly tend to resemble each other in terms of educational levels and job prospects. This issue has important public policy implications since even small changes in both fertility and employment participation can have huge short-term consequences for population size and ageing structure and welfare sustainability.'

Dr Tiziana Nazio, who conducted the research, drew on data from three large-scale longitudinal surveys to model the relationship between periods of work and non-unemployment of both men and women, and the timing of the birth of their children. Her models also included data on the nature of employment, the marital status of couples and socio-economic variables. Data from the UK was compared to the analysis of comparable studies in Italy, where the birth rate and women's employment rates are both lower.

The ESRC will return to the topic of employment and childbearing decisions as part of the longitudinal study, Understanding Society. For the first time participants from forty thousand households will be surveyed about changes in their structure and functions of households, offering a new insight into UK family life.