The decision of leaders of the American Catholic bishops to endorse a state's rights antiabortion measure instead of continuing to fight for federal legislation banning abortion drew fire yesterday from conservatives on the opening day of the hierarchy's annual meeting here.

Cardinal Terence Cooke of New York, chairman of the hierarchy's prolife committee, and Archbishop John Roach of St. Paul-Minneapolis, president of the National Conference of Catholic Bishops, were criticized for testifying earlier this month in favor of a constitutional amendment proposed by Sen. Orrin G. Hatch (R-Utah). The Hatch amendment would recognize the rights of individual states to outlaw abortion.

Though the majority of bishops apparently support that approach, the unexpected flare-up came as Cooke explained that while the prolife committee still had as its ultimate goal a federal constitutional amendment outlawing all abortion, the Hatch amendment "seems capable of passage in this Congress, provided those committed to the protection of the unborn child unite" to work for it.

He appealed to the bishops for "help in informing all of our Catholic people and all prolife Americans" to back the Hatch amendment.

Bishop Joseph Sullivan of Baton Rouge dissented. "I couldn't defend it the Hatch amendment before my people," he said, because "it doesn't live up" to the church's traditional position for a national abortion ban.

Cardinal Humberto Medeiros of Boston, who rarely speaks up in meetings of the hierarchy, was even more emphatic. "I feel with my simple flock in the Archdiocese of Boston -- at least many of them -- I will not be able to tell them why we have changed . . . . In my conscience, I do not see how I could endorse the Hatch amendment which grants power to destroy some innocent life in the mother's womb . . . I would not want to have those innocent voices shouting at me in the future."

But Bishop Joseph A. McNicholas of Springfield, Ill., strongly defended the swing in political tactics. "This is possibly a passable amendment," he said. He challenged the bishops "to realize that eight years have gone by since the Supreme Court decision striking down state abortion laws and we say we are for the unborn, and all the while we been sitting there letting the unborn be slaughtered because we haven't had the political insight to fight for what can be accomplished."

In other actions yesterday, the bishops set the stage for debate over a proposed statement on Central America, which, among other things, opposes U.S. military assistance to El Salvador, calls for U.S. support of a political rather than a military solution to problems there, and urges "a mature, cooperative diplomatic relationship between the United States and Nicaragua."

Archbishop James A. Hickey of Washington, in preliminary discussion, supported the statement as "timely, well founded and responsible." There is, he conceded, "some risk in making any statement" about a situation as volatile as the one in Central America. "But I submit there is a far greater risk in not making a statment . . . . By our very silence we would appear to be walking away from our duty to make a statment in behalf of justice."

But an unusually large number of proposed changes to the statement already submitted by bishops indicates extended debate when the item comes up for final action Thursday.