What was going on when I was born?

Catherine McDermott is being a bit facetious when she calls herself ''the Rosa Parks of fat people.'' But there is nothing frivolous about her lawsuit against the Xerox Corporation, which declined to hire her 11 years ago because she was seriously overweight. In 1974, Xerox approached Mrs. McDermott, then 56 years old, about a position as a systems analyst in its Rochester headquarters. The offer was contingent, however, upon passing a physical examination, and Mrs. McDermott had problems. She stood 5 feet 6 inches and weighed 249 pounds. The company's health services chief, pointing to what he said was the link between obesity and emotional disturbance and the danger it posed to Xerox's disability and life insurance programs, said she should not be hired unless she lost 90 pounds. This is something Mrs. McDermott, who says she has a thyroid condition, was never able to do.

Nancy Reagan and 17 other first ladies today heard speaker after speaker - including a tearful teen-ager - urge that more parents get involved in the worldwide battle against drug abuse. The occasion was the First Ladies Conference on Drug Abuse, which Mrs. Reagan called ''a mother-to-mother conference, rather than a government conference.'' All of the first ladies involved are mothers or grandmothers. Speaking in the East Room of the White House, a former drug abuser named Robin Page, 16 years old, of Cincinnati, told the first ladies she thought that parents of teen-age drug users should step in, as hers did when it became obvious she had a drug problem at the age of 14. They arranged for her, against her wishes, to enroll in Straight, a drug treatment program from which she graduated in March 1984. She is now back in public school, plans to go to college and wants to become a stockbroker or get a government job.

A chart in Business Day on Tuesday with an article about earnings of the American Telephone and Telegraph Company and the seven regional spinoff companies misstated a percentage increase in revenues for the BellSouth Corporation. Its first-quarter revenues were up 10 percent from the 1984 quarter.

President Reagan, declaring that the time had come for the Government to make some ''hard choices,'' appealed tonight to the American public to lobby Congress for passage of a compromise budget that would reduce spending by $300 billion over three years. In a nationally televised address, the President asserted that the Federal deficit posed a threat to a ''sound and powerful economy'' and said he needed the support of the American people to ''help put our financial house in order.'' ''My fellow citizens, the time has come for Government to make the same hard choices your families and businesses do,'' he said. ''The time has come for your public servants to bring spending down into line with tax revenues.'' Senate Vote Likely Today The immediate target of Mr. Reagan's speech was a Senate vote, expected to take place Thursday, on a compromise budget for 1986 that is supported by the Senate Republican leadership and the Administration. The proposal would cut spending over the next three years by about $300 billion, including $52 billion in the fiscal year 1986, which begins Oct. 1.

For ''Sunday in the Park With George,'' a daring modern musical based on a modernist painting, Stephen Sondheim and James Lapine shared the Pulitzer Prize for drama yesterday. Alison Lurie won the prize in fiction for her seventh novel, ''Foreign Affairs,'' and Studs Terkel captured the nonfiction award for ''The Good War: An Oral History of World War II.'' In journalism, Newsday and The Philadelphia Inquirer both won two Pulitzers. And for the first time, there were two double awards: in investigative reporting and feature photography. The awards to celebrate American achievement, now in their 69th year, were announced at Columbia University by the school's president, Michael I. Sovern.

''Yes, the President is going to Bitburg. We are going to Bitburg, period.''

BECAUSE his father was a curator of historical monuments at Versailles, Claude Mougin grew up steeped in classical culture. He traveled extensively in Italy and spent time in Sicily and Greece. So when the French fashion photographer began to think about converting an empty Chelsea loft into a studio for himself and a home for his wife, Mae, and daughters, Solange and Zoe, his theme, not surprisingly, was the ancient ruins of Pompeii and classical Rome. Enlisting the help of Robert M. Lohman, an interior designer, and Pierre Hitier, a painter and muralist, in a collaborative project, Mr. Mougin set about creating his personal version of antiquity. ''The idea was to pass over ultramodern architecture and go back to something simple, quiet and romantic,'' Mr. Mougin explained. ''I didn't want anyone to impose anything wild, aggressive, geometric and hard to live with on the space.''

Two more police officers were arrested and the entire top command of the 106th Precinct in Queens was ordered transferred last night amid new charges that prisoners there had been tortured with an electric stun gun. Earlier, Mayor Koch said he had asked Attorney General Edwin Meese 3d and other Federal officials to open a separate inquiry into the charges of brutality at the precinct station house, which is in Ozone Park. The arrests bring to four the number of officers arrested on assault charges and accused of jolting three prisoners with electric shocks from a hand-held stun gun. The prisoners said this week that they had been burned by the shocks and that they had been forced to confess to having sold marijuana. Lieutenant Is Suspended Police officials also suspended without pay a lieutenant in charge of guarding against brutality and corruption at the precinct.

The Pentagon's Inspector General said today that 45 of the nation's 100 largest military contractors were under criminal investigation by the Defense Department. The official, Joseph H. Sherick, who was appointed to head the Pentagon's oversight activities two years ago after Congress established the post, told members of the House Energy and Commerce Committee's investigations panel that ''anybody who quotes me as saying things are good needs their bolts tightened.'' In another development, 10 present and former workers in the aerospace industry were charged today on 80 Federal felony counts of receiving kickbacks and scheming to defraud their employers in connection with Defense Department contracts. [Page D5.] Mr. Sherick did not name any of the companies under investigation by Pentagon agencies. In recent months, the General Dynamics Corporation and the Pratt & Whitney engine division of the United Technologies Corporation have been subjects of grand jury investigations.

On college campuses around the country yesterday thousands of student protesters took over administrative buildings, boycotted classes and held teach-ins, rallies and marches demanding that the schools end investments in companies doing business in South Africa. At the University of California at Los Angeles, 200 protesters occupied a campus building yesterday, after a demonstration Tuesday by more than 2,000 students, many bearing placards with slogans like ''Apartheid Kills'' and ''Divest Now.'' In Albany, two dozen chanting students staged a sit-in at the business office of the State University of New York's central administration building. And at the University of Madison at Wisconsin, about 200 demonstrators occupied a conference room at the State Capitol.

A mayoral commission's unequivocal conclusion this week that Dr. Elliot M. Gross, the city's Chief Medical Examiner, was ''not guilty'' of ''wrongdoing'' is unlikely to represent the final judgment about an office that has been buffeted by controversy for more than a decade. The commission's investigation was prompted by a series in The New York Times last January that reported, among other things, on allegations that Dr. Gross had engaged or assisted in cover-ups of the deaths of several people in police custody. The series also detailed a history of infighting and administrative turmoil that appear to have undermined the office's ability to function adequately. The commission of lawyers and pathologists, appointed by Mayor Koch, flatly rejected the allegations that Dr. Gross had ''obstructed the investigation and prosecution of custodial cases, by falsifying or obscuring autopsy reports or death certificates.'' Yet it criticized his ''confused handling'' of the case of Michael Stewart, a 25-year-old Brooklyn man who died 13 days after his arrest by the transit police in 1983, and its panel of consultants disagreed with Dr. Gross's conclusions in some other cases.

THURSDAY, APRIL 25, 1985 International Nicaraguan rebels won't get new aid from the United States. The House of Representatives, by a vote of 303 to 123, dealt President Reagan's Central America policy a stinging setback when it killed all attempts to provide additional assistance to the insurgents battling the Sandinista Government. [Page A1, Column 6.] The Pope named 28 new cardinals, including Archbishops John J. O'Connor of New York, Bernard Law of Boston, Miguel Obando y Bravo, the head of Nicaragua's Roman Catholic church, and Henryk Roman Gulbinowicz of Wroclaw, an outspoken backer of Poland's outlawed Solidarity union. [A1:1.] Bob Dole urged the cancellation of President Reagan's planned visit next month to a German military cemetery at Bitburg that contains the graves of 47 Waffen SS soldiers among the 2,000 dead. [A1:5.] U.S.-West German ties would suffer if President Reagan called off a scheduled stop at the Bitburg cemetery, according to Chancellor Helmut Kohl's spokesman. [A19:1-2.] No progress in arms talks in Geneva was made because the United States and the Soviet Union fundamentally disagree over how the negotiations are to be conducted, according to Reagan Administration officials. They said the Soviet side, throughout the opening six-week round of negotiations, refused to bargain on cuts in nuclear arsenals until Washington first agreed to negotiate a ban on research and deployment of space defense weapons. [A6:4-6.] Israeli forces pulled out of the eastern and central sectors of Lebanon, completing the latest phase of the second of three planned stages of withdrawal.