Research Programme

Do marital prospects dissuade unmarried fertility

John Knowles

Project summary


Unmarried fertility was a lot lower in the 1970s than in the 1990s. It was also the case that unmarried mothers had much lower marriage rates than non-mothers, a differential that has largely vanished over time. This project aimed to assess if this ‘marriage market penalty’ for mothers in the 1970’s was strong enough to explain why unmarried fertility rates were lower in the 1970’s than in the 1990’s.


To explore this issue, a new model of fertility and marriage, based on directed search was introduced. Relative to the previous marriage literature, the main contribution is that our model can allow for arbitrarily high numbers of children and transitions in and out of marriage. This means it is relatively straightforward to match our model to annual data and thus measure the importance of these interactions. An application of the model is provided to demonstrate this feature; a numerical analysis of the change in marital regime between 1973 and 1995. In our empirical section, we analyse the 1973 and 1995 waves of the National Survey of Family Growth.


The results demonstrate that the greater importance of marital prospects in the 1970s than in the 1990s may be sufficient to account for the lower birth rates of unmarried women at the time. Findings suggest that the decline, from the 1970s to 1995, in marriage rates of unmarried women with no children, can account for the dramatic rise in unmarried women’s share of births over that period. The quantitative results are not meant to be definitive but rather should be taken as illustrations of the usefulness of this approach; the presence of children has been ignored in most analysis of the marriage market, but these results confirm that the interaction between marriage and fertility is significant.


Project activities

Date Activity Description
1 April 2011 Presentation at the Royal Economic Society Conference held at Royal Holloway. John Knowles presented the paper ‘Marriage, careers and contraception' at the event.



Kennes, J. & Knowles, J. (2012) Do marital prospects dissuade unmarried fertility? CPC Working Paper 23, ESRC Centre for Population Change, UK.


Media activities

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