Women and girls lag behind men in Internet access in many parts of the world, causing them to miss out on the economic and social benefits of being online, according to a new report from Intel.

Across the developing world, there are about 25 percent fewer women than men online, said the report, one of the first to attempt to measure worldwide Internet access by women. In some areas the gap is even greater, with a 43 percent gap in sub-Saharan Africa, a 34 percent gap in the Middle East and North Africa, and a 33 percent gap in South Asia, according to the report.

While many groups have acknowledged an Internet gap between the genders, the goal of the Intel report was to "quantify what that gap is, because that data didn't exist before," said Shelly Esque, vice president of Intel's corporate affairs group and president of the Intel Foundation.

Women miss many benefits if they're not online, she said. "We believe, and I think there's plenty of evidence to support, that the Internet is a gateway to so much opportunity, information around health, education, economic opportunities," she said. "This list goes on and on. If women are denied access to that information, then they're denied opportunity to thrive in their communities."

Promoting better Internet access for women is a good way to help improve economies around the world, added Melanne Verveer, ambassador at large for global women's issues at the U.S. Department of State, which, along with the United Nations and World Pulse, supported the study.

"The dramatic differential in access to the Internet results in fewer opportunities for women to reach their full potential and a loss of significant economic and social contributions to their families and communities," Verveer wrote in the report.

The Intel study found that Internet access can boost women's income. About half of survey respondents use the Web to search for and apply for jobs, and 30 percent have used the Internet to earn additional income, Intel said. The study is based on analysis of global databases and interviews and surveys of 2,200 women and girls in Egypt, India, Mexico and Uganda.

Intel recommended a new global effort to get more women and girls online, with governments and privacy industry working together to bridge the gender gap. The study predicted that an additional 450 million women and girls will come online in the next three years through organic growth, but a concerted effort could bring an additional 150 million online.

Private industry can work to make Internet access affordable and provide more free content that appeals to women, the study said. Governments can develop national plans for increasing broadband penetration, it recommended.

With 600 million more women online during the next three years, nearly a third of them would improve their ability to generate new income, and the new online users could create a market of US$50 billion to $70 billion in IT and telecom sales, Intel estimated.

One barrier to bringing more women online is an attitude among some women, the study said. One in five women in India and Egypt believes the Internet is not appropriate for them, the study said. Some of those women don't believe the Internet has information they need, and others are concerned their families wouldn't approve of them being online, the study said.

Part of the solution is educating women about what's available online and targeting information to groups who need it, Esque said. In some areas, women may be interested in maternal health information, and in other areas, weather and crop information, she said. "Until you know what's possible, it's hard to imagine how this can impact your life," she said. "It's incumbent on all the players, the private and the public sector, to think about, what is that local, relevant information?"

Grant Gross covers technology and telecom policy in the U.S. government for The IDG News Service. Follow Grant on Twitter at GrantGross. Grant's e-mail address is grant_gross@idg.com.