Mexico convinces its people to have fewer children - but growth rate is still high

''It's easier to care for fewer children,'' is the message of television commercials sponsored by the Mexican government in a campaign to drastically cut population growth.

The commercials, which began airing across the nation recently, usually show parents fondly caring for two children while extolling the financial and moral advantages of small families.

The ads come in the second phase of a population-control campaign here that is widely viewed as successful.

The program, which began in 1977, sought to reduce Mexico's soaring population growth from 3 percent a year to 2.4 percent by 1982. That it was successful is seen in the figures on current growth - 2.3 percent a year. Now Mexico aims to cut population growth to 1.9 percent by 1988. (For comparison, the United States growth rate is 0.7 percent, while the world population growth is 1.8 percent a year, according to the Population Reference Bureau, Inc.)

Mexico's early goal was met, the government says, through the combined impact of publicity on family planning, increased contraceptive use by women, rapid urbanization, and the entry of many women into the work force.

The government has honed in on family planning as a key program because it worries that its population growth may cancel its economic progress of the past decade.

''The effects of overpopulation are being felt in every aspect of people's lives, including employment, housing, education, food and health care, which consistently suffer from shortages,'' Secretary of Health Guillermo Soberon Acevedo says.

The imbalance between a high population growth rate of 2.3 percent and a negative 1983 economic growth rate of 4.7 percent already has created a ''devastating problem,'' Mr. Soberon Acevedo says.

Some 800,000 Mexicans enter the work force yearly, but many cannot find jobs. Rural migration continues unchecked because of underemployment in the country-side and land ownership problems. The result is a volatile mass of unemployed migrants swelling slum belts around the major urban centers. Mexico's population has jumped from 56 million to 75 million inhabitants in 10 years, and it ranks as the 11th most populous nation in the world.

Compounding these problems is Mexico's economic crisis. The nation has one of the highest foreign debts in the world - around $84 billion.

Analysts say the second phase of Mexico's planning program, sponsored by the National Population Council, differs from the first in that it puts more emphasis on family planning than on economic development, health, employment, or education. In the first phase all five goals were emphasized.

''The second phase, mentioned in the Conapo (Population Council) report, also stresses the need to integrate women into the work force and to provide better access to education. But I think it places more emphasis on family planning because it's been so successful,'' said Jose Gomez de Leon of the Center for Demographic Studies and Urban Development at the Colegio de Mexico.

Officials admit the goal of reducing the population growth rate to 1.9 percent by 1988 will be difficult.

''It won't be an easy task for three reasons,'' says Manuel Urbina Fuentes, director of the family planning program at the Health Ministry.

''First, the number of women of reproductive age will go up to 21 million by 1988. Second, we will have to reach rural populations, which are not easily accessible. Finally, we have the economic crisis. . . . While it's an incentive for families to have less children, it also means that we might not have the financial resources . . . to carry out our program.''

Another problem, he adds, is machismo. Mexican men still look on children as a sign of virility and few worry about contraception.

''That mentality has changed very little,'' Mr. Urbina Fuentes says. ''We are going to do a survey to find out how Mexican men reason.''

Then, he adds, the government will develop a strategy to change men's attitudes and increase their participation in the birth control program. Youth and rural populations also are being targeted.

The apparently successful program is not without vociferous critics, however. Some observers allege that birth control is imposed without consent.

By law, family planning is a decision left to couples. Population Council official Jeronimo Martinez Garcia says, ''The government merely points out the problems of large families and provides information and help to couples.''

But doctors and representatives of some private family-planning organizations charge that thousands of women have had various forms of birth control, including sterilization, imposed on them in state-run facilities.

A representative of one private family-planning organization says some women have been tricked into signing consent forms for sterilization. Some were told that the forms were authorizations to permit injections of anesthetics, while others were simply pressured into signing the forms, the spokesman says.

Some said birth control devices were inserted without consent while they were under anesthetics used in child delivery.

Health officials say that abuses may occasionally happen, but not often.

A 1982 survey by the Population Council found that voluntary sterilization of women rose 57.9 percent over three years and that government health organizations performed most of the operations.

Officials claim that most sterilizations are performed on women age 35 and over with large families, but the figures also show that among nonsalaried female employees aged 20 to 24, the sterilization rate is 15.8 percent.