A new set of findings from women’s empowerment non-profit LeanIn.Org and online survey platform SurveyMonkey reveal that, since the media reports of sexual harassment first emerged last fall, male managers are three times as likely to say they are uncomfortable mentoring women and twice as uncomfortable working alone with a woman. The hesitation to meet with women outside of work is even more pronounced: Senior men were 3.5 times more likely to hesitate having a work dinner with a junior female colleague than a male one–and five times more likely to hesitate to travel for work with a junior woman.

In a Facebook post Tuesday morning, LeanIn.Org founder Sheryl Sandberg explained that men’s increasing unwillingness to mentor their female colleagues “undoubtedly will decrease the opportunities women have at work.” The Facebook COO pointed out that, “The last thing women need right now is even more isolation. Men vastly outnumber women as managers and senior leaders, so when they avoid, ice out, or exclude women, we pay the price.”

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To encourage more men to mentor their female colleagues, LeanIn.Org Tuesday launched a campaign called #MentorHer. Already, a number of high-profile male business leaders have made the commitment to mentor women, including Oath CEO Tim Armstrong, LinkedIn co-founder Reid Hoffman and CEO Jeff Weiner, Unilever CEO Paul Polman, and Facebook CEO Zuckerberg. Disney CEO Bob Iger gave a Twitter shoutout to ABC President Channing Dungey, saying he was “proud” of her and his other mentees.

https://twitter.com/jeffweiner/status/960914153140494336

I’m proud of Channing and all of my former “mentees,” who are now shaping the future of the industry. #MentorHer. https://t.co/K5NZrm5nBE

— Robert Iger (@RobertIger) February 6, 2018

Gender equality in workplace has come a long way – but we are not done. Access to mentors must be equal so that men and women have the same opportunities to succeed. That’s why I commit to #MentorHer https://t.co/Q270lxplsn

— Paul Polman (@PaulPolman) February 6, 2018

The New York Times’ investigation into allegations of sexual harassment and assault against media producer Harvey Weinstein inspired millions of women around the world to say “me too”—that they, too have experienced unwanted sexual advances or violence. A wave of accusations followed, knocking nearly 100 powerful men off their perches, including actor Kevin Spacey, tech investor Steve Jurvetson, music producer Russell Simmons, among others.

The snowballing effects has led some men to express hesitation about being alone with women. In November, Fox News analyst Brit Hume tweeted: “[Vice President] Mike Pence’s policy of avoiding being alone with women other than his wife looking better every day.”

Far from being a solution, this attitude hurts women; the #MentorHer campaign aims to educate about just why mentorship is so crucial to achieving gender parity in the workplace. Among the powerful statistics the campaign site points out (based on LeanIn.Org’s research):

• People with mentors are more likely to get promoted.
• Women are 24% less likely than men to get advice from senior leaders
• 62% of women of color say the lack of an influential mentor holds them back.

Sandberg writes: “If we’re going to change the power imbalance that enables so much sexual harassment in the first place, we need to ensure women get more mentorship and sponsorship, not less. That’s how we get the stretch assignments that lead to promotions. That’s how we build the networks that put us on the path to exciting opportunities. That’s how we get the respect – and recognition – we deserve.”