The Rev. Charles Curran, professor of moral theology at Catholic University and an internationally recognized critic of church teachings on sexual ethics, met with Vatican officials in secret talks Saturday that colleagues here fear may signal future disciplinary action by the Vatican.

The Vatican's Sacred Congregation for the Doctrine of the Faith has carried on extensive correspondence with Curran since 1979 about his dissent from traditional church teachings on such issues as birth control, in vitro fertilization and abortion.

Curran's meeting in Rome on Saturday with officials of the Vatican Congregation, which took place at his request, "marked a new stage in the investigation of Prof. Curran," according to a statement released by a campus support group, Friends of American Catholic Theology.

Osservatore Romano, the official Vatican newspaper, called the session "an informal meeting, held outside the procedural rules of the congregation." One knowledgeable church source said that meant "it was not a question and answer session."

Curran, 52, who was not available for comment yesterday, will hold a news conference today to talk about his situation.

Curran's longtime scrutiny by the Vatican Congregation, once known as the Inquisition, is well known among fellow theologians, but most were reluctant yesterday to comment publicly.

Members of the theology faculty at Catholic University are in a special category among theologians in the United States because the school is considered a pontifical faculty subject to special scrutiny from Rome.

As a member of that faculty, Curran is subject to the same type of discipline that the Vatican Congregation levied against Swiss-born theologian Hans Kueng when it revoked his missio canonica, the church-controlled license to teach as a Catholic theologian.

This is not Curran's first brush with church authority. In 1967, he was dismissed from the CU faculty for his public dissent from the encyclical by Pope Paul VI upholding the church's ban on artificial birth control. The student body began a protest strike, and after five days Curran was reinstated.

In more recent years, however, Curran's challenge of church doctrine has been criticized by conservative Catholics, many of whom view him as the embodiment of the modernist trends they abhor. A small but extremely vocal movement of Catholic traditionalists has peppered Rome with its views, including the demand that Curran be silenced.