Does a woman’s success damage the ego of her male partner? Perhaps we’d like to think we’ve evolved beyond that, but a recent study suggests otherwise. In fact, in the study, a woman’s success made her partner feel worse about himself than her failure did. Women in the study were unaffected by their partners’ successes (or failures).

“It’s a problem that doesn’t get spoken of very much. What man is going to say, ‘Well, because you are successful, I feel less than’?” said Marion Solomon, a marital therapist in West Los Angeles and co-author of “Love and War in Intimate Relationships.”

In the privacy of the therapist’s office, it’s a different story, said Jill Weber, a clinical psychologist in Tysons Corner. “It’s . . . something that certainly clinicians and therapists see a lot.”

What makes the new study so fascinating, Weber said, is that the men who participated weren’t even aware that their self-esteem was affected by their partners’ performance. This, she said, could cause problems later on. A man struggling on an unconscious level with a partner’s success might suddenly act out — distancing himself from his partner, becoming slow to return phone calls or being less attentive, said Weber, author of “Having Sex, Wanting Intimacy: Why Women Settle for One-Sided Relationships.”

“Maybe they do things that they don’t understand themselves,” she said. “The guy is giving the impression that he’s not that into the relationship, when in reality he’s just trying to protect himself from the fear of rejection.”

It’s all about competition

The study’s lead author, Kate A. Ratliff of the University of Florida, attributed the results to a difference in how men and women respond to competition.

“On average, men are more competitive than women,” Ratliff said. “So it’s definitely possible that men would respond in a self-negative way to anybody’s success.” While it might make sense for a competitive man to feel threatened by being outperformed by a woman, the men in this study felt their partner’s success was their own failure, regardless of whether they were engaged in one-on-one competition.

The men in the study, which was conducted in the United States and the Netherlands, also might have been reacting to culturally reinforced expectations of men’s traditional role of dominance in a relationship, a role threatened by female success, Ratliff said.

The study involved five experiments in which a total of 896 men and women participated. In one, a person was told that his or her romantic partner had scored in either the top 12 percent or the bottom 12 percent in a problem-solving test; then, the person’s self-esteem, both explicit and implicit, was measured. In the other experiments, participants were asked to write about social or intellectual situations in which a partner had succeeded or failed. While all participants expressed positive feelings about a partner’s success, the researchers determined that on a more subtle level, a man’s self-esteem actually fell after he acknowledged that his partner had done well.

The study, whose results were published in the Journal of Personality and Social Psychology, covered three experiments with college-age subjects and two with people whose average age was around 30.

The findings make sense to the University of Connecticut’s James O’Neil, who studies gender-role conflicts and the psychology of boys and men.

“From a masculinity perspective, men are supposed to be the ones that succeed, and certainly for some men they think they should succeed more than women and be better than women,” said O’Neil, a professor of educational psychology. “Men are socialized to be competitive and to win and to succeed.”

Traditionally, men have been expected to take the lead in a relationship, especially financially, and to be the front-runner, said Aaron Rochlen, a professor who studies the psychology of men and masculinity at the University of Texas at Austin.

But increasingly, men are no longer the financial leaders in their relationships. This may not prove to be, as author Hanna Rosin calls it, “The End of Men,” but Rochlen said that among married heterosexual couples, more women are out-earning their partners than ever. In dual-income families, 28 percent of American wives earn more than their husbands, according to Bureau of Labor Statistics data. Many men struggle with that reality, even though they may not admit it.

Men who react negatively to a partner’s success, Rochlen said, are probably hanging on to old-school ideas of what it means to be a man — what Rochlen called “the John Wayne model of masculinity” that a man should have control over a woman, restrict his emotions, avoid vulnerability and be in command at all times, attitudes that don’t square with living in today’s world or being psychologically healthy. Rochlen said such men are more likely than others to suffer broadly in relationships and beyond. He noted that there’s much research showing that holding on to outdated male stereotypes and behavior is a major predictor of high levels of substance abuse, acting out, depression, anxiety and other problems.

That women in the experiments had no problem with a man’s success can be explained in a couple of ways. The study’s authors noted that whereas men are inclined to be competitive, women are more likely to identify with a partner in a nurturing way and therefore less likely to be threatened by her partner’s success.

Undoing a long history

Solomon offered a different interpretation: Longtime gender roles may also play a part in a woman’s unfazed positive reaction to a male partner’s success. “Women had been trained in our culture to see themselves as a support system for the husband. And if he is successful, they are successful. We’ve had 3,000 years of history saying you’re supposed to be with a man who’s a little taller, a little smarter and a little richer. And you can’t change that in one generation.”

Rochlen said that as more women rise to power and success supported by husbands or partners whom people admire, this will help modify societal beliefs about men, women and success.

In the meantime, how should couples navigate the tender subject of self-esteem and partner success?

Solomon suggests that a man who’s feeling ill at ease over a partner’s success needs reassurance of his or her worth. She said back before the women’s movement, the smartest men were the ones who made sure to acknowledge the importance of the woman behind the man. The same applies today to men with successful female partners. “What you want to do, no matter how successful you are — and I say this to women and to men — [is] make sure that the person you are committed to knows that you feel very fortunate to be with them, ” Solomon said. “Tell them, ‘Here are the things I appreciate about you.’ ”

Allard Levingston is a writer based in Bethesda.