I haven’t seen such statistics, and I don’t know if we can refute it by economists’ standards.
Are you familiar with the story of St. Lawrence, who was a deacon and martyr of the third century? A high Roman official commanded St. Lawrence to surrender the treasures of the Church. St. Lawrence agreed to do this, but instead of the expected silver and gold, he presented the poor whom he had gathered and said, “These are the treasures of the Church.”
What is treasure? Economist measure wealth in terms of gold, silver, and money. They look at those who have very little and call them “poor”. In contrast, Blessed Theresa of Calcutta remarked on abortion, “It is poverty to decide that a child must die so that you may live as you wish.”
Many in my country (USA) have lots of material wealth, yet think they can’t “afford” more than two children. Contraception is the norm, and abortion is legal. Contrast that to some Catholic countries where may have less money, but more children. Who is really richer?
Those who push contraception and family planning often hold up misleading statistics as if more stuff makes a better life. It doesn’t. Some wish to rob the poor of the one treasure that they do have: their children.
So, it’s entirely possible that in Catholic countries where contraception is not practiced, economists find more “poverty”. Yet, if they considered children valuable, they would find such countries far “richer” than in countries where abortion and contraception are commonplace.