Elaine Wynn has donated $1 million to the women’s health organization, Fortune has learned. “As a woman, a mother, and a grandmother, I’m proud to do what I can to help protect access to reproductive health care,” the billionaire said in an emailed statement.

Wynn credits her decision to donate to last month’s Women’s March on Washington, as well as Facebook (FB) COO Sheryl Sandberg’s decision to donate the same amount. “I’m a firm believer in the importance of women helping women, and as a longtime supporter of Planned Parenthood, I know that they’ve done so much to help women get the health care they need,” Wynn said.

Wynn is the co-founder of Mirage Resorts and Wynn Resorts, and is currently worth $1.84 billion, according to Forbes. The donation will be split between the Planned Parenthood Federation of America and Planned Parenthood of the Rocky Mountains, the affiliate that serves Las Vegas, where Wynn resides.

Planned Parenthood president Cecile Richards said via email that the organization has seen an uptick in donations since Donald Trump’s election. While campaigning, Trump threatened to defund Planned Parenthood and said that there should be “some sort of punishment” for women seeking abortion if it were to be outlawed. He also promised to nominate to the Supreme Court a pro-life justice who would overturn Roe v. Wade, the landmark 1973 reproductive rights decision that protects a woman’s right to end her pregnancy. However, it is not yet clear what the stance of nominee Neil Gorsuch is, as the justice has never ruled explicitly on the issue of abortion.

“Since the election, we’ve seen a tremendous outpouring of support by so many people willing to donate their time, money and energy to help Planned Parenthood,” Richards said. “The American people overwhelmingly support Planned Parenthood and strongly oppose ‘defunding’ care at Planned Parenthood.”

The organization has received more than 400,000 donations from across the country, according to a spokesperson (who declined to share the total dollar amount of these donations).

While the added funds undoubtedly help, Richards said that they “will never be able to replace the reimbursements we receive from federal programs for health services.” She noted that shutting down federal support for the program “would deny millions of people—nearly half of whom are people of color, and many people who live in rural areas— the health care they rely on. Shutting down Planned Parenthood would create a national health disaster for women.”

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Last month, President Trump reinstated the global “gag rule,” which bars international NGOs that perform or promote abortions from receiving U.S. government funding. It was this ruling that spurred action from Sandberg, who wrote a Facebook post in which she voiced her opposition to the ruling:

“We don’t have to guess—we know what this will do,” she wrote of Trump’s executive action. “The last time the global gag rule was in effect, research showed more women who lost access to contraception had unwanted pregnancies and abortion rates doubled. The best way to prevent abortion is through more family planning services, not fewer.”