Pope Goes Barnstorming With Birth Control Plea : Mexico: He delivers his message in a country whose government actively seeks to limit population growth.

A tireless Pope John Paul II barnstormed through bruising heat and buoying crowds in the Mexican north Thursday to deliver an uncompromising message against artificial birth control to a nation whose government aggressively seeks to limit population growth.

John Paul spent three hours in Chihuahua, enough time for 600 new babies to be born in Mexico where the population, now around 83 million, has grown by about 16 million since the Pope’s first Mexican visit in 1979.

Pilgrims from El Paso, Tex., 225 miles to the north, joined hundreds of thousands of festive Mexicans at a wind-whipped outdoor service in a dusty field here in Chihuahua, an agricultural and mining state of copper-colored hills, endless blue sky and wide-brimmed cowboy hats beneath an unblinking summer sun.

An afternoon Mass in a dry riverbed at industrial Monterrey took John Paul to within 100 miles of Laredo, Tex., his closest stop to the United States on an eight-day Mexican pilgrimage that ends Sunday.

Once again Thursday--Mother’s Day in Mexico--huge friendly crowds stalked John Paul’s every step through a day that began early in Durango and ended late in Mexico City.

In a modern society scarred by “violence, abortion, euthanasia, the marginalization of the disabled and the poor,” John Paul said, it is the woman who “is called to keep alive the spark of life, the respect for the mystery of all new life.”

Terming Catholic marriage a “demanding reality,” the Pope said that Roman Catholic couples must always be open “to the gift of life.”

“You must keep in mind that if the possibility of conceiving a child is artificially eliminated in a marriage, the couple is shutting itself off from God and opposing his will,” the Pope said in reiterating the church’s unbending opposition to artificial birth control.

“Furthermore,” he said, “the husband and wife close themselves off from each other because they reject the mutual gift of fatherhood and motherhood, reducing the conjugal union to an opportunity to satisfy each other’s egotism.”

The church-state split over population policies in Mexico is a variation on a theme that courses through all countries of Catholic Latin America.

The church, whose teaching allows only natural methods of family planning, is at odds with a Mexican government whose development efforts are compromised by a mushrooming population. There will be 100 million Mexicans by century’s end in a nation struggling to lift living standards for a people whose average annual income is now only around $2,000.

Government birth control programs, criticized by Catholic groups, include television ads urging couples to limit themselves to two children.

The programs have helped to reduce the population growth rate to 2.4% a year. Even that, though, means about 2 million births per year and--with about 40% of Mexicans under age 15--a doubling of the population in 29 years.

About 96% of Mexicans are professed Roman Catholics, but 48% of Mexican women now use contraception, according to International Planned Parenthood. In the United States, about 85% of Catholic couples ignore the church teachings on birth control that the Pope reaffirmed Thursday.

Telling Chihuahua worshipers that the health of a society depends on the health of its families, John Paul urged greater respect for the rights of children, including the unborn.

“Society is more sensitive every day to the rights of the child,” the Pope said. But he warned that any child is nevertheless still a potential victim of a long list of ills, including “the evil of a part of society that makes attempts on his life even before birth through the practice of abortion.”

Today, the Pope travels to extreme southern Mexico for visits to Chiapas and Tabasco states, where he is expected to address refugee issues.