How the Vatican Almost Embraced Birth Control | Mother Jones

"...Then, in 1966, Paul VI's birth control commission presented its preliminary report to the pope. It held big news: The body had overwhelmingly voted to recommend lifting the prohibition on contraceptives. (The former Archbishop of Brussels, Cardinal Leo Suenens, went so far as to say the church needed to confront reality and avoid another "Galileo case.")

Catholics rejoiced, and many began using the pill at once. But their hopes were dashed when, in July 1968, Paul VI released an encyclical titled Humanae Vitae ("on human life"), reaffirming the contraceptive ban. It turned out that three dissenting bishops on the commission had privately gone to plead with the pope: If the position on contraceptives was changed, they said, the teaching authority of the church would be questioned—the faithful could no longer trust the hierarchy..."

http://www.motherjones.com/politics/2010/05/catholic-church-vatican-bishops-birth-control