The organisers of the Women's Ordination Worldwide conference being held in Dublin said the 350 delegates showed courage in turning up given the "climate of fear" surrounding the issue within the Roman Catholic Church.
Keynote speaker and Nobel Peace Prize winner Ms Mairead Corrigan-Maguire said Catholic clergy were "forbidden" from discussing the issue of women's ordination and described this as a "form of spiritual abuse".
Ms Soline Vatinel, spokeswoman for the conference, said: "Because of the climate of fear now permeating the Church community, coming to such a gathering takes courage and love. What will the Church be tomorrow if it doesn't allow dialogue on women's ordination? A patriarchal remnant."
Opening the conference, held at University College Dublin, Ms Maguire said: "Since 1996, when the Pope reaffirmed the Roman Catholic Church's stand on priestly ordination of men only, this was made a doctrine of faith and theologians and religious may not speak about this matter.
"I believe this kind of attempt to control by the Vatican is an abuse of power. It is dehumanising, demoralising and is a form of spiritual abuse."
She said Catholics grew up in a "sexist church" which conditioned people to accept only male priests.
The Vatican's reasoning, she said, was that Jesus is said to have chosen only male apostles. She added: "For a long time, I have believed that woman's ordination in the Catholic church will happen, it is only a matter of time."
Ms Vatinel, of Brothers and Sisters in Christ, said the original keynote speaker, MS Anuna Gnanadason, of the World Council of Churches in Geneva, was forced to withdraw in May following pressure from the Vatican.
Rev Rose Hudson-Wilkins, a member of the Church of England, told the conference: "In every denomination there are women who know deep in their hearts that they are being called before God to live out their baptismal call.
"Yet there are those in authority who are apparently safeguarding the faith who know more than God and who dare to say that they know the will of God and women play no significant part in that.
"We may be told that we are strident for pressing the church to keep this issue on its agenda but we have been the ones who are the true guardians of the faith."
PA