Since the U.S. is basically the only developed nation in the world that does not guarantee paid leave after the birth of a child, it's up to individual employers to determine whether they will offer anything above the unpaid six weeks required by law.

As a result, just 13 percent of American women receive any kind of paid leave through their employer, according to the U.S. Department of Labor.

Yet research links maternity leave to higher employee retention. Google, which was one of the first major companies to offer an extended maternity leave to six months in 2007, concluded that the rate at which new mothers quit was cut by 50 percent thanks to the improved policy. At my company, we've found a direct correlation between women's overall job satisfaction and the amount of maternity leave taken.

More and more companies are using enhanced paid leave programs to support gender equality and working parents. In 2016, at least 23 major companies--like Nike, Bank of America, Coca-Cola and Chobani--announced dramatically enhanced programs. (My company has been tracking them--you can see our data here.)

If you are wondering what makes a good paid leave program, there are a few elements:

1. It's 100 percent paid.

For many years, companies have stopped short of offering their female employees paid leave in the U.S. While their jobs remain protected, women lose their income during the time they take off from work after childbirth.

It's a terrible double-whammy: At a moment when their household expenses increase dramatically, they lose up to a quarter of their annual income.

Even companies with generous paid leave programs sometimes pro-rate the bonuses or commission plans, which still stacks up to lost income.

This premise is already problematic: It would be most generous--and competitive--to pay parents during leaves as an outstanding company benefit. But it becomes downright unfair when parents on leave work from home while they're "away."

As one friend told me: "I checked in regularly and took phone meetings during both my leaves, even while I wasn't paid. That meant I was effectively working for free in order to preserve my job. That just left me feeling taken advantage of."

2. It's for women and men. And adoptive parents, too.

I recently spoke with Lorna Hagen, SVP People Operations at small business lender OnDeck. She refers to her program as "baby-bonding" leave to emphasize that it's not just for women who have given birth; it's a benefit for all parents to adjust to a new family member.

Some of the most notable leave policies announced in 2016--including American Express and Etsy--are equal in length for men and women. A 2010 research study by the University of Oslo linked fathers taking paternity leave to improving children's performance at school.

In 2015, Facebook CEO Mark Zuckerberg gained national attention for taking two months off after the birth of his daughter. Zuckerberg's leadership in this space should be applauded. If a male CEO can take time off without negatively impacting his company, anyone can.

3. It's at least 12 weeks.

New parents (female and male) lose an average of six months of sleep in the first 24 months of the lives of their children. I can attest first-hand that sleep deprivation is indeed a form of torture.

It's also hard to perform well at work, especially while basically having two jobs: one as a professional and one as a parent.

Taking twelve weeks off--without the stress of lost income--helps parents get the rest they need and adjust to their new role and responsibilities at home.

4. It applies to all employees.

In August 2015, Netflix announced a 52-week parental leave policy, applying both to women and men. The generous policy applied only to salaried employees--meaning it omitted hourly employees, most of whom worked on the DVD side of the business. Netflix impressively took responsibility for this oversight and by December 2015 had updated its policy to include hourly employees as well.

Ikea's recent announcement of offering up four months paid parental leave to employees regardless of gender was also notable due to the scale at which it will provide paid leave to hourly employees.

5. Employees can take leave without being penalized.

At my company, we've observed an interesting phenomenon: Law firms tend to have some of the most generous maternity leave policies available--some as high as 22 weeks paid. Still, their employees don't feel they can take the time off without risking career progress or employment.

As one lawyer reported to us: "People take maternity leave, but I think that people are discouraged from taking the full leave and full paternity leave when they are close to being up for partner."

One of my great wishes for 2017 is more parental leave for more new parents. I firmly believe it's the right thing for both American families--especially the children--and American businesses.