On the eve of a U.N. conference to appraise the progress of the world's women during the past decade, the stage has been set here for a political confrontation between Third World countries and the United States.

The North-South, rich-poor schism that appears likely to dominate, and possibly derail, this 10-day gathering of delegations representing 155 nations was put in stark relief by two blunt speeches last week.

In Washington, President Reagan dispatched the U.S. delegation, headed by his daughter Maureen, to Nairobi with these words: "The members of your delegation firmly believe that the business of this conference is women, not propaganda. Should it prove necessary, you'll be more than willing to fight to keep the conference on track. Take it from someone who knows Maureen, that's the way it is going to be."

By "propaganda," Reagan was referring to global political issues, such as the creation of a Palestinian state, apartheid in South Africa, Third World condemnation of Zionism and demands in the developing countries for a so-called new international economic order that would improve their terms of trade with rich countries such as the United States.

"Legitimate women's concerns," Reagan said, were "all but pushed off the agenda" by these political issues at previous U.N. women's conferences in Mexico City in 1975 and Copenhagen in 1980.

In Nairobi on Friday night, Margaret Papandreou, the American-born wife of Andreas Papandreou, the Socialist prime minister of Greece, said the United States had no right to tell the world's women what their concerns should be.

In a flat Illinois accent that voiced sentiments of delegations from many Third World and Eastern Bloc countries, Papandreou told a press conference that the U.S. delegation would not be able to control the conference. "No one group of women can determine what are women's issues and foreclose discussion on non-women's issues, as that group defines them," she said.

In a parliamentary maneuver yet to be resolved, the U.S. delegation is attempting to keep "non-women's issues" from dominating the conference by changing the rules under which final resolutions can be adopted.

The United States has demanded that they be adopted by "consensus," which it interprets to mean unanimous vote, rather than by majority vote. The change would allow the United States to block adoption of any offensive final report by the conference.

Delegates spent several hours tonight haggling over the U.S. insistence on the "consensus" rule. The meeting was adjourned with no agreement having been reached, according to a U.N. spokeswoman. Efforts will be resumed Monday to resolve the issue, which a U.N. source said could "stymie" the entire conference the first time any delegate calls for a vote on any issue.

In Copenhagen, where adoption was by majority vote, the United States was one of four countries -- with Israel, Australia and Canada -- that voted against the final 287-paragraph document. The primary objection was a paragraph that called Zionism a form of racism.

The U.S. strategy to require consensus voting at the conference was outlined in a background paper issued in February by the Heritage Foundation, a conservative Washington-based think-tank.

The consensus rule "would give the U.S. (or any other delegation) veto power over politically motivated resolutions or sections of resolutions. Such a rule worked rather well at the U.N.'s second special session on disarmament in 1982," the report said. It also called on the United States to "threaten to withdraw from the proceedings should the legitimate agenda be ignored."

Upon her arrival in Nairobi Friday afternoon, Reagan was asked about that possibility. She said only that the "United States is prepared to work for an excellent document outlining women's concerns until the year 2000."

A U.S. diplomat in Nairobi, however, said recently that for the United States to pull out of the conference "it would have to get rough, it would have to get absolutely absurd, and a lot of countries would have to pull out, too."

In Nairobi last week, a number of feminists, including former congresswoman Bella Abzug and Papandreou, said it was unfortunate but true that the official delegates to the conference, who are almost all women, have little independence and will be controlled by their governments, most of them controlled by men.

The U.S. delegation, while maintaining that it is here to focus on those women's issues which, in President Reagan's words, are "of the greatest importance," has not singled out family planning as one of its four main areas of concern for the world's women. According to a U.S. diplomat here, domestic politics in the United States, particularly the fear of upsetting conservatives, prevents the inclusion of family planning as one of the delegation's "focus" issues. Instead, it will focus on women's literacy, women in development, domestic violence and refugee women.

"If we could somehow loosen that cord between women here who feel obliged to speak only as their governments speak," Papandreou said, "it would be a most rewarding and refreshing conference."

Although political issues appear likely to dominate the conference again, there has been considerable movement over the past 10 years -- the U.N. Decade for Women -- on other issues highlighted by U.N. women's conferences.

In education, the gap is closing between boys and girls in school attendance, according to a 1985 U.N. report. The improvement has been greatest in developing countries, where girls now are 41 percent of the secondary school population, up from 37 percent in 1975.

The wage gap between men and women, the report said, also has narrowed: women in manufacturing now earn 73 percent of what men earn, compared with 70 percent a decade ago.

A fertility survey in 31 countries found that, within one generation, family planning campaigns have dramatically affected the number of children that women want. The average number fell from six to four. In Africa and in other Third World areas, awareness of the need for family planning and demand for contraceptives has increased sharply, according to family planning specialists.

The number of developed countries with laws requiring that men and women receive the same pay for the same work jumped from 28 in 1978 to 90 in 1983, according to the Commission of the European Community. In developing countries, many donor nations have recognized that women do the majority of farm work and it is they, not men, who should be the target of development programs.

Wife-battering has emerged in the past decade as a major legal and social issue, with tough new laws and more serious police enforcement in many countries and U.S. states.

While noting these gains, the conference is also focusing on what has not changed in the past decade.

The Copenhagen conference report concluded in 1980 that: "While women represent 50 percent of the world population, they perform nearly two-thirds of all working hours, receive only one-tenth of the world income and own less than 1 percent of world property."

Last week, Leticia R. Shahani, U.N. assistant secretary general for the conference, said that conclusion "remains appropriate."

The U.N. report said women continue to be concentrated in lower-paying, lower-prestige occupations than men. Women are increasingly offered part-time work, which has few benefits and little job security, it said, and women and children account for most of the world's refugees, with female refugees, particularly, subject to physical abuse and rape.

In politics, the United Nations (which itself has only three women among its 37 assistant secretaries general) found that there has been "no consistent increase over the decade in women's participation in politics. Costa Rica, Venezuela, Sri Lanka, India and Kenya are typical, with women taking less than 6 percent of places in government."

Ironically, the conference is being hosted by Kenya, a country with the highest national birthrate in the world (4 percent) -- and a place where men, especially in rural areas, exercise nearly total control over the lives of their wives.

Thirty percent of the women in Kenya are married to men who have more than one wife. Wife abuse in rural Kenya is common, according to family planning specialists here, and is considered by many Kenyans, both men and women, to be a normal part of married life.

The Kenyan government has spent at least $1.5 million to prepare for the conference. It has repaved much of downtown Nairobi, painted bright white lines on many of the city's streets and assigned hundreds of police and soldiers to patrol the streets, which normally are considered unsafe at night for pedestrians.

Kenya's "patron" for the conference, Kenneth Matiba, minister for culture and social services, said the government "does not want the conference to fail on Kenyan soil" and has promised to remain neutral in the expected disputes between Third World countries and the United States. Kenya receives about $125 million a year in aid from the United States.

An intriguing aspect of the buildup here to the women's conference has been the attempts of Kenyan politicians and press to praise the event without upsetting the traditional preeminence of the Kenyan male.

"Men Are Reassured," said a headline last week in the Standard, a Nairobi daily. The news story on meetings here of nongovernmental women's organizations (NGOs), running concurrently with the U.N. conference, began with this sentence: "Men should not worry about the outcome of deliberations of the NGO Forum '85 taking place at the University of Nairobi."

Kenyan President Daniel arap Moi, in a speech last week praising women as the backbone of society, urged them to be proud of themselves, in part because "great men and statesmen are born of women throughout the world."