2018 Vanity Fair Oscar Party – Arrivals – Beverly Hills, California, U.S., 04/03/2018 –  Amazon CEO Jeff and wife MacKenzie Bezos.
2018 Vanity Fair Oscar Party – Arrivals – Beverly Hills, California, U.S., 04/03/2018 – Amazon CEO Jeff and wife MacKenzie Bezos. Reuters / DANNY MOLOSHOK

Billionaire philanthropist MacKenzie Scott donated $275 million to women's healthcare provider Planned Parenthood, the largest gift from a single donor in the organization's more than 100-year history, Planned Parenthood said on Wednesday.

The donation, which is part of Scott's pledge to give away the majority of her wealth, was made to Planned Parenthood's national office and 21 regional affiliates.

Scott, who is now married to Dan Jewett, a Seattle science teacher, received a 4% stake in Amazon.com Inc as part of her divorce from Amazon founder and billionaire Jeff Bezos.

Planned Parenthood, which provides abortions and other healthcare services at its clinics around the country, is at the forefront of the political battle over abortion rights playing out in U.S. state legislatures and courts.

Abortion access in the United States is on the decline as Republican-led states pass ever tighter restrictions on the procedure, including a near-total ban on abortions in Texas that has withstood legal challenges.

The conservative-leaning U.S. Supreme Court seems likely to overhaul constitutional protections for abortion this spring.

The court has signaled its willingness to reinstate a ban on abortions after 15 weeks of pregnancy in Mississippi. That would contradict the landmark 1973 Roe v. Wade case that established the right to have an abortion before the fetus is viable, which is around 24 weeks.

"We are incredibly grateful for Ms. Scott's extraordinary philanthropic investment in Planned Parenthood, as a critical part of the public health infrastructure," Planned Parenthood Chief Executive Alexis McGill Johnson said in a statement.

"This funding will support our efforts to advance health equity by eliminating racial and structural barriers for our patients in the communities where Planned Parenthood works."

In a Medium post on Wednesday, Scott said she had donated more than $3.8 billion to 465 non-profit organizations, including Planned Parenthood, since last June.

"Our team's focus over these last nine months has included some new areas, but as always our aim has been to support the needs of underrepresented people from groups of all kinds. The cause of equity has no sides," she wrote.

On Tuesday, Habitat for Humanity announced that Scott had donated $436 million, which will go toward the organization's efforts to boost affordable housing and Black homeownership.

Scott was worth about $49 billion as of Wednesday, according to Forbes.

(The story is refiled to fix spelling of "McGill" in paragraph 8)