NEW YORK — It took just hours for the protests against Susan G. Komen for the Cure to begin, and they quickly took on the fury and form of a full-blown movement.

Online petitions were started. Calls poured forth to withhold donations from Komen for its de-funding of Planned Parenthood, and money was pledged to make up for the lost funds. And on Facebook, Twitter and even YouTube, the shock and anger was palpable.

And then, in barely three days, it was over.

Komen, which supports advocacy and research to find a cure for breast cancer, announced Friday that it was reversing its decision to suspend funding for Planned Parenthood. The organization gets money from Komen for breast cancer screening and other breast-health services for low-income, uninsured and under-insured women. But Planned Parenthood also provides birth control and abortion services, which has made it a target of attacks from Republicans in Congress.

“We will continue to fund existing grants, including those of Planned Parenthood, and preserve their eligibility to apply for future grants, while maintaining the ability of our affiliates to make funding decisions that meet the needs of their communities,” Komen’s founder and chief executive, Nancy Brinker, said in a statement Friday morning. The foundation is named for Brinker’s sister, a Jewish woman who died of breast cancer in 1980.

The widespread outrage that Komen’s initial move sparked in the Jewish world and beyond is a sign not just of the intensity of the passions surrounding breast cancer advocacy, but also of the perils of allowing political considerations to influence public health policies.

With its popular Race for the Cure events and ubiquitous pink ribbons, Komen has established breast cancer awareness as a cultural touchstone. Since its founding in 1982, it has raised more than $1 billion to fight the disease, a cause that has endeared the organization to countless Jewish women. Ashkenazi Jewish women are 10 times more likely than Americans in general to carry a particular genetic mutation that makes them susceptible to breast cancer. In Israel, breast cancer is the leading disease among women.

Komen has been a nonpartisan cause, and its move on Tuesday to drop Planned Parenthood, which is under congressional investigation for allegedly using government money to fund abortions, was seen as an effort to avoid problems with donors.

But the blowback to that move ended up being even more of a problem for Komen.

The National Council for Jewish Women accused Komen of putting “politics before women’s health.” The Religious Action Center of Reform Judaism said the decision was “directly and unfairly threatening the health and safety of women.” The Joint Action Committee for Political Affairs, a bipartisan Jewish group, said that Komen appeared to be “caving in to political pressure.” And Hadassah, which partnered with Komen to organize the first Race for the Cure event in Israel in 2010, said it was “disappointed” that the controversy was distracting from the objective of promoting women’s health.

On Friday, after Komen reversed itself, the president of Hadassah, Marcie Natan, said, “Komen should never again allow this type of controversy to erode the integrity of its well-known and much-admired name in fundraising for breast cancer treatment research and awareness.”

Many of groups that had criticized Komen earlier in the week praised it on Friday for doing the right thing even as they warned that the fallout from the controversy may have some lingering effect.

“I think people are just going to be very wary going forward,” said Nancy Kaufman, the NCJW’s CEO. “People will be watching. I think they will still organize Race for the Cure, maybe a little less enthusiastically.”

Komen’s initial decision to break with Planned Parenthood was made, the organization said, as a result of a policy that prohibited it from supporting groups under federal investigation. But critics claimed that the group had instituted the rule specifically to exclude Planned Parenthood.

Komen vehemently denied the charge, but several news reports suggested that the move was driven by Komen’s new senior vice president for public policy, Karen Handel, a vehemently pro-life former Georgia gubernatorial candidate who has said she opposes the mission of Planned Parenthood. Komen’s top public health official resigned in protest over the decision.

Brinker, Komen’s founder and a Texas Republican and former Republican Jewish Coalition leader who had been honored in December by the Reform movement for her breast cancer work, labored to contain the fallout.

In a YouTube video posted Thursday, she first defended the decision as part of a wider overhaul of granting guidelines. By Friday morning, she had reversed course entirely, apologizing for the decision and promising that Planned Parenthood would remain eligible to apply for future grants.

“We have been distressed at the presumption that the changes made to our funding criteria were done for political reasons or to specifically penalize Planned Parenthood,” Brinker said. “They were not. Our original desire was to fulfill our fiduciary duty to our donors by not funding grant applications made by organizations under investigation. We will amend the criteria to make clear that disqualifying investigations must be criminal and conclusive in nature and not political. That is what is right and fair.”

Brinkner ended her statement with a plea to “help us move past this issue.”

But even for some of the group’s longtime supporters, that may prove difficult.

“I think that they really damaged their credibility, and I hope that they can clean themselves up,” said Rani Garfinkle, a longtime Jewish community activist who participated in several Race for the Cure events, including the inaugural Jerusalem race.

“I’m not sure I won’t seriously reconsider how I give my money,” Garfinkle said. “But it remains to be seen.”