Promoting women could hurt your career—if you’re female. Senior women who help female employees advance are more likely to get negative evaluations from their bosses, a recent study of hundreds of company executives shows.

The research adds to evidence that for women, even seemingly straightforward career choices are rife with potential negative consequences. Other studies show that a woman’s career suffers if she doesn’t have a professional advocate, sometimes referred to as a sponsor. The repercussions for older women who champion female upstarts, however, might limit the number of women willing to play that role.

So young women should just find a male sponsor instead, right? Not exactly. Seek career guidance and support from a man, and you may be accused of participating in an affair or worse, according to, yep, more research (PDF).

Sponsors are crucial to success because, unlike mentors, whose roles are often limited to providing guidance, they’ll use their influence to advocate for rewards on your behalf. Sponsors make people more likely to ask for raises, get promotions, and be happy at work, according to research by the Harvard Business Review (PDF). You need a sponsor, researchers concur.

The HBR report found that fewer women had sponsors than men did, and that women suffered as a result. Researchers also figured out why women were reluctant to cultivate intense relationships with men in power.

“Sponsorship, which often involves an older, married male spending one-on-one time, often off site and after hours, with a younger, unmarried female, can look like an affair,” the report said. “If the woman is subsequently promoted, her achievement will be undermined by office gossip that she earned it illicitly.”

That’s if a sponsor or mentor relationship even comes to pass. Men and women alike may be less likely to want to mentor a woman. A study this year led by Wharton School researcher Katherine Milkman found that university professors were more likely to respond to e-mails from students looking for mentoring if those students were male. Of the 6,500 professors surveyed, those at business school had the strongest prejudice against women, the authors said. Women were also less likely to help out other women, the study found, perhaps imagining the bad rap they might get for doing so.

To sum up: Younger women need sponsors to thrive at work, but they may be penalized if the ones they seek out are male. If they get help from female mentors, those women may see their careers damaged. Also, a young woman may not find a mentor at all, since both women and men are less likely to take them on than men with the same qualifications.

In other words, ladies, career success is yours to grab. Just know that doing so might hurt your career.

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