The current method uses 'excess' embryos from couples trying to artificially conceive in-vitro.
The Vatican on Tuesday welcomed a new way of extracting stem cells that does not use human embryos, calling it a significant advance that could help medical research without going against Roman Catholic beliefs.
Cardinal Javier Lozano Barragan, head of the Vatican's Pontifical Council for Health Pastoral Care, said the discovery showed medicine can progress without destroying human embryos.
U.S. researchers reported on Sunday that stem cells found in the amniotic fluid protecting babies in the womb were nearly as powerful as embryonic stem cells in producing adaptable cells that scientists hope can someday transform medicine.
The Catholic Church and other religious groups have been staunch critics of the most common method of stem cell research, which involves extracting cells from human embryos, because they believe such organisms are humans from the moment of conception.
"I am very glad to see this progress in the field of science for the good of humankind," Barragan told Vatican Radio on Tuesday, noting it did not violate "the life of the donor."
In an interview with the Italian daily La Stampa on Monday, he called the discovery "a very significant and ethically admissible advance" in the search for cells that can create muscle, bone and other cells to replace damaged ones.
Barragan said the Vatican was not opposed to all stem cell research. "The Church is not obscurantist and is always ready to welcome real scientific progress that neither threatens nor manipulates the sources of life," he said.
"Our task as a church is not to oppose the oratory (that is, faith) and the laboratory (or rather, science), nor to transform science into faith," he said.