A high profile Vatican magazine has denounced how male cardinals and bishops treat nuns as lowly servants.

The March edition of Women Church World, the monthly women's magazine of the Vatican newspaper L'Osservatore Romano, accused the Catholic hierarchy of widespread exploitation of nuns for cheap or free labour.

It is highly unusual that a Vatican publication would dare to publicly criticise how bishops treat their nuns, many of who take vows of poverty, receive no pay because they are members of female religious orders and are sent to the residences of male Church officials as part of their assignments.

Quoting unnamed nuns the magazine described how some work in the residences of 'men of the Church, waking at dawn to prepare breakfast and going to sleep once dinner is served, the house is in order and the laundry cleaned and ironed'.

A nun identified only as Sister Marie described how sisters serve clergy but 'are rarely invited to sit at the tables they serve'.

The boldness of the magazine, which is a monthly supplement to the Vatican daily newspaper Osservatore Romano, has led to it being seen as the home of the Vatican's #MeToo movement.

'Until now, no one has had the courage to denounce these things,' the magazine's editor, Lucetta Scaraffia, told The Associated Press. 'We try to give a voice to those who don't have the courage to say these words.'

In a recent interview she said simply: 'Inside the church, women are exploited.'

One nun said she knew of fellow sisters who had PhDs in subjects such as theology and had been, with no explanation, ordered to do domestic work or other chores that had 'no relationship to their intellectual formation'.

The experiences of such nuns, the article said, could be transformed 'into a richness for the whole Church, if the male hierarchy sees it as an occasion for a true reflection on power (in the Church)'.

Scaraffia, a Catholic feminist and professor of history at Rome's La Sapienza university, is one of very few women to hold senior positions within the Vatican hierarchy.

Additional reporting by Reuters.