Family structure has an impact on the welfare of children, according to the latest part of a comprehensive Government-sponsored study on children.

The report cites research showing that children in one-parent families “are likely to do less well on a number of child development indicators than children in two-parent families”.  

Report 5 of the Growing Up in Ireland study, a longitudinal research project examining the progress of two cohorts of children, acknowleges that there is evidence suggesting that “particular forms of family structure may influence the circumstances and developmental outcomes of children”.  

And it also notes that changes in family structure, especially what it calls relationship transitions “have a negative effect on children’s behavioural, socio-emotional and cognitive outcomes”.

Referring to children raised in one-parent families compared with two parent families, it cites a 2001 study showing that “problem behaviours were more frequent among children from unmarried than married families, and more frequent for boys than girls from cohabiting families”.  

It also cites Irish research which suggests that “one-parent families have been identified as having the highest risk of poverty and deprivation”.

The reports says that these effects might be mediated by a number of factors, such as the level of economic resources available to the family, presence or absence of male role models, the impact of family structure on mother’s physical and mental health, and the time available for supervision and parenting.  

“Furthermore, the wider economic and cultural climate prevailing at the time has the potential to moderate these mechanisms,” it suggests.

The report also acknowledges that the number of children being raised outside marriage has grown significantly in Ireland in recent decades.  

It notes: “In 2002 there were 77,600 cohabiting couples in Ireland, increasing to 121,800 in 2006 (CSO, 2006) and 143,600 in 2011 (CSO, 2012)…..Ireland has also seen substantial growth in the percentage of non-marital births since the early 1980s, from approximately 5 per cent to over 33 per cent by 2011.”

The report, which specifically looks at children aged three and under, says that 85pc of all children in its research group lived with both biological parents.

The report said: “Just under 15pc (of the three and under cohort) were in one-parent families, with seven per cent having one child only.”

It adds: “The impact of both initial family form as well as the dynamics of family structures on the child’s development will be examined in subsequent reports.”