Pope Francis has warned married couples who choose not to have children that they are heading for an old age blighted by "the bitterness of loneliness".
In a homily on Monday in the Vatican guesthouse where he lives, the Argentinian pontiff railed against "a culture of wellbeing" which he said had convinced some people they were better off shunning procreation and getting a pet instead.
"This culture of wellbeing … convinced us: 'It's better not to have children. It's better! That way you can see the world, go on holidays; you can have a house in the country and be carefree," he said.
"Maybe it is better, more convenient, to have a little dog, two cats; and the love goes to the two cats and the little dog."
But such couples were destined to rue their ways, Francis said. "Eventually this marriage gets to old age in solitude, with the bitterness of loneliness. It is not fertile; it does not do what Jesus does with his church: he makes it fertile."
Francis, 77, was holding a special mass at the chapel at the Domus Sanctae Marthae for 15 couples who had been married for between 25 and 60 years, Vatican Radio reported.
He told them fertility was one of the three planks of a successful marriage, alongside faithfulness and perseverance.
"Married life must be perseverant …because otherwise love cannot go forward," he said. "Perseverance in love, in good times and in bad times, when there are problems: problems with the children, economic problems, problems here, problems there – but love perseveres, presses on, always trying to work things out, to save the family."