The Women's March, in contrast, has previously been supported by abortion organizations including NARAL Pro-Choice America, but amid controversy over anti-Semitism allegations, NARAL and other groups are no longer supporting Saturday's event.
"You know, it's not just about speeches that we give or where we show up", Pence told attendees of the March for Life annual Rose Dinner.
'I think the most risky thing we ever did is make this a partisan issue, ' said Destiny Herndon-De La Rosa, 35, president of New Wave Feminists to the Washington Post.
"This pro-life administration, across the board, we've been working every day, to keep our promise to stand with all of you, without apology, for the sanctity of human life", the vice president said. He also sent a letter to Congress warning them he would veto any legislation loosening restrictions on abortion rights or "that encourages the destruction of innocent human life at any stage".
Every year thousands of men, women, college students, children, and babies gather in Washington D.C. for the March for Life, marking the anniversary of the Roe v. Wade Supreme Court decision.
"We've got a record of extraordinary progress on the right to life", the vice president said.
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Since then, United States officials and Trump himself have suggested the withdrawal would be slower than initially thought . President Donald Trump said the group had been defeated there and that he would pull out all American forces.
Tom McClusky, president of March for Life Action, said in a statement after Trump's announcement, "We are so grateful to hear directly from President Trump today that he will be steadfast in his commitment to protect the most institutional of pro-life provisions".
As President, I am committed to defending the Right to Life.
"I look forward to a time when every child - girl or boy, with special needs or special mind - has the opportunity to enjoy life, liberty, and the pursuit of happiness", he wrote.
Speakers at this year's rally include Congressman Dan Lipinski, a Democrat, and Congressman Chris Smith, a Republican. "This will be the generation that restores the right to life in America". The media "will ignore us", Shapiro continued, and will pay more attention to "the five who show up tomorrow", referring to the Women's March scheduled for January 19 in Washington. Thankfully, the number of abortions has been on the decline in recent years.
One marcher said she had an abortion when she was 15 but had been opposed to abortion ever since the birth of her first daughter.