Marriage does not improve children's development

20 July 2011

New research published by the Institute for Fiscal Studies, and funded by the Nuffield Foundation, finds little or no evidence that marriage itself has any effect on children’s social or cognitive development.

This calls into question the idea that supporting marriage through the tax system, which the Prime Minister has repeatedly expressed his desire to do, would improve children’s cognitive or social development.

Marriage does not improve child development

Ellen Greaves, Research Economist at the IFS, and one of the authors of the report, said: “It is true that children born to married couples are on average more cognitively and emotionally successful than children born to cohabiting couples. But careful analysis shows that this largely reflects the differences between the types of people who decide to get married and those who don’t.

"On average those who marry tend to come from more advantaged families, and are more cognitively and emotionally successful themselves, than those who cohabit. This explains the differences in outcomes for children. Marriage itself appears to confer little, if any, benefit in terms of child development.

New evidence

The IFS published initial research using data from the Millenium Cohort Study (MCS) last year and have now completed additional analysis to ensure the effect of marriage had not been underestimated. 

Researchers used data from parents' own childhoods to identify differences between couples before they entered into the relationship into which their child was born. After controlling for these differences, they found no significant difference in the development of children born to married parents and those born to cohabiting parents.

This confirms findings from earlier research by the IFS that parental age, education, and income are more important factors in child development than marriage.

Researchers found that parental cognitive ability was the most significant factor in children’s development. The higher average cognitive ability of married parents over cohabiting ones explains about one fifth of the gap in the cognitive development of children.