The Philadelphia chapter of the Susan G. Komen Race for the Cure says registration for its annual race on Mother’s Day is down by about 18 percent over last year, reflecting lingering displeasure over the national organization’s blunder in February.

Komen, the powerful breast-cancer philanthropy based in Dallas, was forced to reverse a ban on funding to Planned Parenthood’s breast-health programs after blistering outrage from people who buy pink-ribbon products and run in Komen’s fund-raisers.

“National made a misstep,” said Elaine Grobman, chief executive officer of Komen’s Philadelphia affiliate. “They apologized. They told us affiliates that it will never happen again. But we do need to regain the trust of the community.”

By last week, almost 18,000 people had signed up for Philadelphia’s Race for the Cure, compared with 22,000 by the same time last year, Grobman said. Traditionally, 10,000 more register on race day. This year, the May 13 event will have a 5K run, 5K walk, a mile walk, and a new feature, a kids’ dash.

Around the country, news stories have reported that race participation and donations are down as much as 30 percent at a number of Komen’s 122 affiliates, including central Indiana, southern Arizona, and southwestern Florida.

In February, when Komen’s defunding decision became public, founder Nancy Brinker said the grant award process was being made more rigorous; Komen would no longer give money to groups that were under federal investigation. Planned Parenthood happened to be the subject of an inquiry launched by U.S. Rep. Cliff Stearns, an antiabortion Republican from Florida.

Critics denounced the decision as a politically motivated sop to abortion foes. Komen had no trouble taking donations from sponsors under investigation, such as Bank of America, the critics noted, while giving grants to other institutions facing investigation, including Pennsylvania State University, with its child sex abuse scandal. Donations poured into Planned Parenthood, far exceeding the $680,000 it received from Komen in 2011.

Ironically, most of Planned Parenthoods’ 79 chapters have not sought Komen funding in recent years because the family-planning organization focuses on clinic-based gynecological care, while Komen’s community health grants stress breast cancer outreach and education programs for “underserved” women, especially minorities and immigrants. Planned Parenthood chapters in Southeastern Pennsylvania, Bucks County, South Jersey, and Delaware have not applied for grants for two years or more, Grobman said.

Last month, Komen announced awards to 17 Planned Parenthood chapters for the fiscal year beginning April 1, about the same number as before the controversy erupted.

Contact Marie McCullough at 215-854-2720, mmccullough@phillynews.com or @repopter on Twitter.