NEW YORK (Reuters) -- Nearly half of all U.S. businesses are run from home, and most companies owned by women are home-based, according to a new government report.

The data, showing 56 percent of female-owned businesses are run from home, illustrates how women opt to work from home for an array of family reasons, workplace experts said.

Among businesses owned by men, less than half, or 47 percent, were home-based, said the U.S. Census Bureau report.

"A significant percent of women having businesses in the home are comprised of women who are doing it for family reasons," said Kathleen Christensen, director of the Workplace, Workforce and Working Families program at the Alfred P. Sloan Foundation in New York.

They may include not only women with children but women who left the mainstream workforce and find it difficult to return or older women starting businesses, she said.

"It's really an untapped labor pool for many American employers because many of these women would, in fact, be in the labor pool for hiring if, in fact, there was more flexibility that would allow them to pursue their careers in a challenging way but also have a satisfying family life," she said.

Working from home, particularly among women, may appear to solve work-family problems but presents its own issues, said Robert Drago, professor of labor studies and women's studies at Pennsylvania State University.

Home-based businesses tend to be uncertain sources of income, for example, while working at home is difficult with small children and married women's home-based work tends to be taken less seriously than their husbands' jobs outside the home, he said.

But given the economic trend toward outsourcing and subcontracting, he said, more people will be likely to run businesses from home, he added. "The problem is it doesn't solve work-family conflicts in the best way," he said. "I and anybody else who studies work-family issues have real concerns about how that affects women."

The Census Bureau found 49 percent of the nation's businesses are operated from home. Also, three-quarters of U.S. businesses are self-employed individuals with no paid employees, it found.

The report was based on information collected from more than 2.3 million firms as part of a survey of business owners, part of the bureau's 2002 Economic Census, conducted by mail among a random sample of U.S. businesses.