In her recent book Work. Pause. Thrive., journalist Lisen Stromberg documents extensively how women struggle in the workplace after having children, due to what she describes as a Motherhood Bias. Motherhood Bias causes women to be underestimated, underpromoted and underpaid after having children because of assumptions about their dedication to -- or availability for -- the responsibilities of their jobs.

According to Stromberg, although it is rarely discussed, Motherhood Bias is a clear culprit as to why women drop out of the workplace in droves during childbearing years -- particularly from high-performance career tracks. And those who remain at work feel the need to conceal their family responsibilities -- as if any mention of them will leave them penalized.

Management consulting firm Accenture is working to combat this Motherhood Bias in its daily practices. At Accenture, female leaders abound (the company just announced a new goal -- 25 percent women managing directors by 2020), and leaders are not afraid to talk about how they are business leaders and mothers all at the same time. Instead of sidelining women who become mothers or asking them to conceal their "motherhood" status, Accenture embraces working mothers as high-performing employees and also as parents.

For example, Accenture's Kim Cleaves, managing director of talent acquisition for North America shares that her fierce loyalty to Accenture was solidified when she became pregnant with triplets and was forced to be on bedrest. Instead of writing her off, her managers supported her thoroughly as she worked remotely throughout the rest of her difficult pregnancy. When her three boys were born, Kim had her hands full -- but she says that throughout her tenure at Accenture, she's always been able to be a hands-on mother without sacrificing her career. In fact, even while she was working part-time after returning from maternity leave, she was promoted twice.

As another example, Kathleen O'Reilly, who is senior managing director for the U.S. Northeast, said that despite a heavy travel schedule, "I'm always a mom. This is a lifestyle, this job, but technology allows you to be creative. I am always on FaceTime." She added that Accenture has extended its leave policy -- and she learned by her third child that "it's a good thing to take your maternity leave." O'Reilly flouts convention by regularly taking her young children with her on her global business trips.

Eliminating "motherhood bias" so that women can thrive during the challenging years when they have small children must be an essential part of the talent strategy for any company that wants to improve its gender diversity numbers.

Here are three key policies Accenture has in place to create a workplace that is explicitly supportive of working mothers:

1. Flexibility

The consulting industry often requires a lot of travel -- but at Accenture, women are encouraged to work locally for up to a year when they return from maternity leave. Kim says this policy has been received with rave reviews. Accenture also offers part-time work, compressed workweeks and telecommuting options.

2. Emphasize a "truly human experience."

Accenture's chief leadership and human resources officer Ellyn Shook emphasizes that employees should be able to bring their whole selves to work. "When our people are operating from a position of strength, they will perform better."

3. Embrace Transparency.

Accenture was the first large professional services company to publish its diversity statistics. Cleaves says that publishing this information externally helps keep them driven and on track. "Unless we're going to be transparent about it, we really can't improve it. We're reporting out on it so we need to be accountable," she says.