Using such epithets as "shameful," "stupid" and "terrible," White House critics gathered on Capitol Hill yesterday to denounce the administration's opposition to the global advisory code intended to protect Third World children from diseases and malnutrition resulting from promotion of infant formula.

But they spared President Reagan personally, alleging that his aides have kept him from getting the full story and expressing hope that if he had all the facts he would reverse the U.S. position at the World Health Assembly (WHA) in Geneva.

"I don't believe that Ronald Reagan wants to see babies die," Rep. Tom Harkin (D-Iowa) said at a news conference called by a dozen House members.

They emphasized that Reagan still could order a "yes" vote by the United States in today's final vote in the WHA. Member nations will endorse the code overwhelmingly. In preliminary balloting yesterday, they approved it, 93 to 3. The two nations that voted "no" with the United States, Bangladesh and Chad, did so for procedural reasons, and are expected to vote "yes" today.

The United States contends that adoption of the non-binding code here would violate constitutional protection of commercial speech.

Like several of the House critics, Sen. Edward M. Kennedy (D-Mass.), presiding at an unofficial "forum" yesterday, contended that most Americans will disapprove of the "shameful" vote cast by the United States. He accused the White House of taking its cues from the American corporations with formula-producing subsidiaries: Abbott Laboratories, American Home Products and Bristol-Myers.

Sen. Mark O. Hatfield (R-Ore.) said the administration "runs the risk of sending a message that we are indifferent to the value and sanctity of human life."

"Absurd and stupid," said Rep. Jonathan B. Bingham (D-N.Y.). "Terrible," said Rep. Frederick W. Richmond (D.-N.Y.). If the U.S. view prevailed, said Rep. Ronald V. Dellums (D-Calif.), the result would be "teh death and murder of millions."

Witnesses with experience in developing countries -- a priest, a nun, pediatricians, nutritionists and actress Kinda Kelsey, a star of television's "Lou Grant" series -- charged that promotion of formula leads to 1 million deaths a year. Manufacturers and the administration declined invitations to testify at the informal hearing.

Religious leaders made some of the strongest attacks. Bishop P. Francis Murphy, auxiliary bishop of the Roman Catholic Archdiocese of Baltimore, said the U.S. vote "is an act of subtle violence against the human rights" of infants and mothers.

Rabbi David Saperstein of the Union of American Hevrew Congregations said the administration seeks "absolutist" protection worldwide for the commercial speech of formula producrs while being satisfied with more "relativist" protection for the political speech of citizens of authoritarian countries. "Misery and death" will result for little children from the first position and for political prisoners from the second, he charged.

For the National Council of Churches, Louis Knowles said U.S. opposition to the code may undermine this country's traditional leadership in the World Health Organization and lead Third World nations to assume a lack of concern in Washington "about the conduct of our corporations in their countries."

At both the forum and the news conference, spectators applauded two Agency for International Development officials, pediatricians Stephen C. Joseph and nutritionist Eugene Rabb, who announced that they had resigned in protest of the U.S. vote, as they had said they would.

Kelsey, recently returned from a tour of five Asian capitals, told of finding a Bangladesh family of 13 with a monthly income of $34 that had been "sold" on bottle-feeding its youngest member at a monthly cost of $28. The result, she said, will be a severe dilution, with contaminated water, of such formula as can be afforded.

University of California pediatrician Davida Coady said, "I don't see how an administration that talks so much about 'right to life' can show so little concern about the right to life of these 1 million babies."