According to the U.S. Census, the number of single mothers increased 25 percent over the last decade - to 7.6 million women nationwide. The portion of these women who are working also grew, from 63 percent to 73 percent.

What is the secret to success for single working moms stretched thin - and for safety in their workplaces? Linda Mason, president and CEO of Bright Horizons Family Solutions, points to three main pillars: "a partner in parenting, a friendly employer and reliable child care."

According to one study, the number one job perk sought by both men and women is flex-time, which is often essential for meeting child care needs, according to an article in the Silicon Valley/San Jose Business Journal.

More and more, companies are recognizing that offering flexible schedules not only reduces turnover, but makes employees more productive (and more alert and safer) when they are at work, according to Circadian Technologies. While flexible schedules are often critical for single parents, these are often just as important for families with two working parents who are struggling to meet family, school and other child care demands.