Valeria Olivarez had no clue what it meant to be antiabortion the first time she attended the March for Life in Washington three years ago. She was just 14 and didn’t quite know what it meant to have an abortion.

But after looking at graphic images of aborted fetuses in pamphlets handed out at a pre-rally conference back then, she understood and decided: She could never support abortions.

Olivarez, 17, attended her third-consecutive Youth Rally and March for Life, with 18 other youths from her Chicago church, St. John Bosco Parish. They traveled 14 hours by charter bus to join more than 17,000 youths at early morning Masses at the Verizon Center and D.C. Armory and a march to the Supreme Court on Monday — the 39th anniversary of Roe v. Wade, the seminal case that legalized abortion in the United States.

The Catholic Church has increasingly focused on educating and mobilizing its youth base around its antiabortion ideology. The rally and march, hosted by the Archdiocese of Washington, drew busloads of Catholic schoolchildren from across the metropolitan area and the country.

Such events reinforce recent Gallup polls that report more young people, especially those in the 18- to-34-year-old range, are identifying as antiabortion.

“The youth are at the heart of this,” said Cardinal Donald W. Wuerl, the archbishop of Washington, who spoke at the Verizon Center on Monday. “They are just so important to us. We try to get them energized with that passion in the morning.”

Most of the youths in attendance from Olivarez’s church, ranging in age from 12 to 18, said the antiabortion programming at the rally this year or in the past was their first real exposure to the issue.

“I didn’t know what an abortion meant until I saw those pictures,” Olivarez recalled. “But now I do, and I think it’s important for me to be here.”

President Obama’s election in 2008, and his subsequent backing of a woman’s right to choose, prompted many to take action. With another presidential election looming, many antiabortion advocates at the event said educating youths in their ideology is more important than ever.

At the morning activities, bishops flanked the boards of the Verizon Center as youth groups, including some from as far as Australia, completely filled the stands. T-shirts sported sloganssuch as: “Abortion is mean,” “One heart stops, another heart breaks” and “Give life a chance.”

Olivarez’s parish joined more than 400 other young adults from Chicago in wearing blue T-shirts that declared simply “I am pro-life.” Sitting at the top of row 217, the group was somber during Mass but laughed quietly when a priest advised the crowd on the virtues of chastity. They said they viewed the rally as less important than the pending march with tens of thousands of protesters marching to the Supreme Court.

“It just sort of hypes you up,” Merlen Mendoza, 18, said. “It’s like a religious pep rally.”

They made signs for the march the day before and were excited to unveil them as they filed out of the Verizon Center shortly before noon. Most bore messages about the sanctity of life, some written in Spanish, others in English.

Mendoza’s brother, Jesse, 14, carried the most controversial of the signs. Not-so-jokingly referred to as the “extremist” of the group, Jesse had drawn a fetus and gushing blood on his sign. Jesse wanted to attend the rally last year but was told he was too young. This year, he was the one who started the groups on chants such as “Jesus” and “Obama, your mama chose life.”

The Chicago group had prepared nonviolent ways to handle encounters with abortion rights demonstrators but didn’t encounter any sizable opposition. Freezing rain, which caused delays and closings around the Washington area Monday morning, may have been a factor. Rally organizers said it limited their own attendance.

Group chaperone Karina Franco, 37, said this was the first real education in antiabortion ideology for most of the youths, some of whom reacted strongly at a conference Sunday when they looked at images of fetuses. Merlen Mendoza stopped eating her sandwich midbite Monday when she saw a screen on Constitution Avenue showing similar images.

As the group wrapped around in front of the Supreme Court, the cheering quieted, and the Chicago students merged with groups from around the country. The group did not stay to hear House Speaker John A. Boehner (R-Ohio) deliver remarks; they were on a tight deadline to board buses Monday night back to Chicago. Many also had plans to visit some museums before heading back.

“It’s important to come here and make sacrifices,” Mendoza said. “But we can also have some fun.”