Rep. Susan Brooks (R-Ind.) has announced that she will retire from Congress. (Alex Brandon/AP)

Rep. Susan Brooks, the head of House Republicans’ recruitment, who had prioritized mobilizing GOP women to run for office after significant losses in 2018, said Friday that she won’t seek reelection.

The Indiana congresswoman, one of only 13 women in the House GOP caucus, stunned colleagues and party leaders when she announced plans to retire in a letter to supporters and in an interview with the Indianapolis Star.

Brooks, 58, told supporters in the letter, obtained by The Washington Post, that she was stepping down to spend more time with her family, including her grown children and aging parents.

“There will be much, MUCH, conjecture about my decision. I’ve made a lot of career changes, but none with the kind of public scrutiny this will attract,” she wrote. “The pressure to be everywhere and speak to every issue and event is immense — it is a part of the job that is difficult to turn off. So I salute those who spend decades running, winning, and serving.”

With Brooks’s planned departure and Rep. Liz Cheney (Wyo.), the House GOP conference chairwoman, mulling a run for the Senate, Republicans face an even greater challenge to shore up their female contingent after losing half of its members in the last election. The House is the most female ever, but 89 of the 102 seats are held by Democratic women, including Speaker Nancy Pelosi (Calif.).

The numbers reflect not only the GOP struggles to recruit female candidates but also the gender gap for the party, which has seen an erosion of support, especially in the suburbs. In 2018, 59 percent of female voters picked Democrats compared with 40 percent who chose Republicans, according to exit polls.

Cam Savage, a political adviser to Brooks, said House GOP leaders were saddened by her decision but asked her to stay on as recruitment chair through 2020.

“She does feel an obligation to help improve Congress and for her that means more women and women playing a greater leadership role, but she doesn’t see an inconsistency with this decision,” Savage said.

Savage credits Brooks and Rep. Elise Stefanik (R-N.Y.) with speaking openly about Republicans’ problem recruiting women, both as candidates and as voters. According to data from Brooks, 172 GOP women are running for the House.

“When we look back, Susan’s legacy will be that she played an instrumental role in leaving our new Republican majority far more diverse than it was when she found it,” said Rep. Tom Emmer (R-Minn.), chairman of the National Republican Congressional Committee. “Susan has assured me that she will be increasing her recruitment efforts, so we are full steam ahead.”

Winning for Women, a group created in 2017 to help elect GOP women, is in the early stages of recruiting for 2020 — next week it will launch its 20 in 20 initiative to get 20 GOP women back in the House.

“Our goal is to see more Republican women in Congress, and we believe it’s a top priority to find a woman to fill her seat,” said Olivia Perez-Cubas, the group’s communications director.

Democrats placed Brooks on its retirement watch list earlier this year. Though she won reelection by 14 percentage points, Democrats figured they had a chance in a district north of Indianapolis that included the kind of wealthy suburbs Democrats did well in last cycle. At the time, Republicans called the notion that Brooks could retire, “laughable.”

Cheney, in a statement, praised Brooks and dismissed the notion of Democrats winning the seat that Brooks won in 2012 after a competitive GOP primary.

“While I’m confident Indiana’s 5th District will continue to have strong and principled conservative leadership going forward, I know Susan’s voice and passion will be sorely missed in our conference,” she said.

Democratic Congressional Campaign Committee Chairwoman Cheri Bustos said Brooks’s retirement is endemic of the House Republican caucus’s problem recruiting and retaining women.

“As the ranks of women in the House Republican caucus continues to shrink, it must be disappointing to lose such a strong advocate for Republican women,” Bustos said.