When the children were five years old, the women were asked about how much their husbands did around the house, including helping with housework, childcare and shopping.
Just over half didn’t help at all – or only assisted with one task.
A quarter carried out two tasks, and the remaining quarter did three or four, the journal Feminist Economics reports.
Around 7 per cent of the couples had divorced by the time the child was ten, rising to 20 per cent by the youngster’s 16th birthday.
When the two pieces of information were crunched together it became clear that the more a man helped out, the more stable his marriage was.