The Vatican has ended a controversial probe of the Leadership Conference of Women Religious, a group of American nuns it deemed too feminist and political. Above, Sister Pat Farrell (right), former president of the group, and Sister Janet Mock, the executive director, after a meeting with Cardinal William Levada at the Vatican, June 12, 2012. Reuters/Max Rossi

The Vatican has officially concluded a review of a group of U.S. nuns that it had deemed too feminist and political, and straying too far from Catholic doctrine. The review was supposed to run until 2017 but ended Thursday after a meeting between leaders of the group and top Vatican officials.

It remained unclear, however, what conclusions the review drew and what changes, if any, would be made. The investigation into the group, the Leadership Conference of Women Religious, began in 2012, under current Pope Francis's predecessor, Benedict XVI. The conference is an umbrella group that represents about 80 percent of nuns in the U.S.

"We are pleased at the completion of the [investigation], which involved long and challenging exchanges of our understandings of and perspectives on critical matters of life and its practice," Sister Sharon Holland, the president of the conference, said in a statement. "We learned that what we hold in common is much greater than any of our differences."

The Vatican suggested in statements that it was trying to allow both sides to move past the controversial review. Cardinal Gerhard Müller, who leads the office that conducted the review, said his office was "confident that LCWR has made clear its mission to support its member institutes."

In April 2012, after a four-year investigation, the Vatican's doctrinal office, the Congregation for the Doctrine of the Faith, accused the nuns of concentrating on issues that were too distant from, or incompatible with, traditional doctrine. "These sisters collectively take a position not in agreement with the church's teaching on human sexuality," it said, and it also noticed "a prevalence of certain radical feminist themes incompatible with the Catholic faith." The office also frowned upon how many nuns were advocating for U.S. health care reform, Religion News reported.

The announcement of the Vatican review in 2012 sparked backlash and controversy, and after being elected to the papacy in March 2013, Pope Francis had generally been expected to end the review ahead of its slated deadline.