Businesses need women. It's simple, inarguable math: job shortages are irrefutable, skills are in demand, and women make up more than half of those on college campuses earning degrees. There are also the economic indicators: women, it has been shown, are good for business.

So it's no surprise that some historically male-dominated specialties - law, consulting, and tech among them - are taking definitive steps to reevaluate their approaches to retaining women. Most recently the law firm Fish & Richardson announced additions to its benefits programs aimed specifically at helping women come back to work after a baby.

"Returning to work with an infant at home," sized up a Fish principle succinctly recently when announcing the new programs, "presents immense obstacles."

Under the Radar Obstacles that Cost

Retaining women comes down to identifying those obstacles - and getting them out of the way. It's not always easy since they're often under the radar - and they're not always about the job. Accenture's Julie Wilkes once described what many nursing mothers in her company called the "awkward and uncomfortable challenge" of bringing milk home from business travel. "They have to go through the airport, and figure out how to get their milk on planes," she told us. The same mothers often wrestle with things like pumping at work - not the kind of problem typically discussed in job interviews.

But such practical matters of motherhood take their toll. And when they become too much - when milk pumped during travel routinely gets thrown away; when new mothers find themselves nursing next to the boiler because that's the only private space available at the job - many women decide it's easier just to stay home.

What Really Chases Women from the Workplace

That more companies are taking note says that they're recognizing what really chases women from the workplace. The age-old hypothesis that women prefer stay-at-home motherhood turns out to be false. Thousands of women in our Modern Family Index (MFI) said categorically that coming back was their preference; 96% said they were eager to.

That doesn't mean the transition is easy. Women also told the MFI they worried about post-baby careers and feeling judged and looked on as less committed. Response's like Fish's - today they provide milk shipping, career mentoring, and child care to ease the transition for new mothers on leave, among other things - address those concerns. The efforts do more than merely help women dodge individual stumbling blocks. They also send an unequivocal message - that working mothers are welcome.

One successfully re-engaged new mom calls that message the key element in her decision to return to her job. "Before I went out, my manager made it clear that he wanted me to come back," she said. "That said a lot."

For organizations that need women, that alone is a powerful retention tool.