A prenup sets out how a couple will divide assets if they divorce.
Harry Benson, Research Director at the Marriage Foundation, was speaking to Premier's News Hour after a law firm suggested an increasing number of couples were signing the agreement pre-wedlock, particularly as some parents are contributing towards buying homes or mortgage payments.
He told Premier he does not think lots of people are signing the pre-marriage agreements.
He said: "We're probably talking about one per cent or two-to-three per cent at most of the entire population of couples getting married. So, I suspect this is affecting very small numbers of people, anyway."
The research by JMW Solicitors said half of the prenups they write are at the request of the parents.
Harry Benson said he was not keen on the idea: "I think the whole idea of a prenup is utterly ghastly.
"By going into a marriage expecting to fail or thinking about failure before you even start, you're stacking your odds against you in the first place"
He went on: "Getting married in the first place massively increases your odds of staying together.
"Committing in the first place is great but I think signing a piece of paper which says, 'I'm going to get to keep all my toys in the case where we break up' is such an awful idea, I can't imagine why anyone would actually do it".
Listen to Premier's Aaron James speak to Harry Benson here:
