Hey CEOs: Hire women if you want to boost revenue

Microsoft CEO Satya Nadella said last week that women should stay mum about asking for raises and instead trust "the system" and karma for pay rewards— ironically at an event focused on women in tech.

After a social media outcry, Nadella apologized. But a new study asserts that there's a bigger reason for CEOs to take gender diversity seriously than just quelling the masses—the bottom line.

LDProd | Getty Images

Workplaces that are evenly split along gender lines are more productive and help the company's financial performance, compared to offices that lack gender diversity, according to the study co-authored by an MIT researcher. And all-male or all-female workplaces that shifted to a more balanced gender ratio increased revenue by roughly 41 percent.

The findings are based on analysis of eight years worth of revenue and employee survey data from an undisclosed Boston-based professional services firm operating more than 60 international offices, each with two to 19 employees.

Sure, the findings may be specific to one firm in one industry, but they're a clear indication that "companies really need to start considering whether introducing more diversity could in fact benefit their bottom line in ways they may not be able to predict or understand," said Sara Ellison, the study's co-author and an MIT economics senior lecturer.

Read MoreSarah Silverman's gender pay gap solution? Crowdfunding

"A man told me he used to work in an all-male firm 20 years ago," Ellison said. "They started the day out talking about the Patriots for half an hour. Now that the workplace is more balanced, they just exchange pleasantries and get straight to work."

However, the study found that in a more homogeneous office, workers are happier, more cooperative and had higher morale. But these data points did not mean the homogeneous employees performed better or made the company more money.

Think of it like this: If a football team hired only quarterbacks, they'd have a great time relating to one another, exchanging tips and equipment. But such a team would not perform as well as a one with a full roster of players.

Read More Powerful women on how to fix tech's gender problem

It's hard to guarantee that gender diversity will lead to a greater range of skills and ideas, but it's safe to say men and women bring unique experiences and viewpoints to the table, Ellison said.

In the tech industry, there is overwhelming evidence that when there is more gender diversity, innovation and critical thinking flourishes, said Vivek Wadhwa, a tech entrepreneur and fellow at Stanford Law School.

"Imagine how much more the tech industry could achieve if they worked harder to include women. What we see now could be nothing compared to what is possible," Wadhwa said.

Nadella's gender gap pay disaster
Nadella's gender gap pay disaster

Wadhwa criticized the tech world for not taking responsibility to reform hiring practices that favor men.

Read MorePenney's new CEO separates retailer from the pack

"What companies do is they make a small half-million-dollar donation to a girls' coding group or host in-house diversity groups," Wadhwa said. "Half a million is like a quarter to you and I. It's all just a smoke screen for them to be able to essentially do nothing."

It will certainly take more than lip service or donations to offset tech's male-skewed demographics. At Microsoft, said recently that only 17.1 percent of tech workers are female. Twitter had the lowest, with women representing only 10 percent of tech employees, while eBay had the highest, at 24 percent, according to gigaom.com.

Read MoreHow 'cool' would it be if more kids were psyched about STEM?

But with tech companies already enjoying high earnings and revenue without much gender diversity, the study is not likely to be a major turning point in the sector, said Jon Bischke, CEO of Entelo, a recruiting firm that uses predictive analytics to identify specific types of talent. Entelo clients include Microsoft, Facebook and AOL.

The longer companies remain skewed toward male workers, the harder it will be for the firm to recruit women, Bischke said. Companies should prioritize recruiting women or training them for leadership roles, which sparks a trickle down of female hires through the corporate ladder.

"The study may not be a huge influence in tech to hire more women but someone may bring it back to their company to show that, look, gender diversity's not only the right thing to do, it's the profitable thing to do."