Women now comprise about half the US workforce, according to a major story in the December 30 issue of the Economist. In other words, half our workforce bears all our children. Anyone who wants a child of one's own must recognize that somewhere, a woman will bear that child and will likely nurse him. However, lack of paid maternity leave places half our workforce at risk for economic insecurity or even frank poverty, just because they happen to have two X-chromosomes.

So, attention all employers, coworkers, and legislators: If you want to have a sustainable workforce, at some point, you will need more workers. Furthermore, if you do not wish for humans to go extinct, you have to accept women's role in propagating our species. In other words, all us humans all share the responsibility for supporting maternity leave and supporting the ability of working moms to nurse their infants.

Maternity leave is really not so different from any kind of leave. All employees, young and old, male and female, will require leave at some point in their working lives. It may be to recover from surgery, or care of a sick spouse or aging parent. The Family and Medical Leave Act recognizes that, even though employees aren't paid during their leave.

Recently, when I tried to make a doctor's appointment for my kids, I learned that my kids' doctor was out on leave, recovering from a hip replacement. Although I was disappointed, my first thought was, "good for him!" For years I had watched this older man hobble around the office in pain, and I'm so happy he'll finally get relief. Will his experiences as a patient make him a better doctor? Of this, I have no doubt.

When I took time off to care for my dying mother six years ago, I became a much better physician for it. I struggled valiantly to relieve my mom's pain, spooned meds in her mouth like she was a baby, and cleaned up her vomit when she could hold nothing down. Now, whenever I meet with the family of a dying patient, my profound empathy shows through, and is much appreciated. In short, I am a much better employee because I took that time off, not to mention a better daughter.

We use a similar argument to justify why employers should be proud to let their employees out for a month to serve in the National Guard or Reserves. They are building useful skills as well as serving their country. A 1994 federal law, the Uniformed Services Employment and Reemployment Rights Act (USERRA), guarantees that civilian employers reemploy military personnel who serve up to a total of up to five years, provided they have appropriate documentation.

Mothers have a valuable skill set; we are able to multitask in a way that perhaps we couldn't before we had children. Pretty quickly, mothers learn how to handle a screaming toddler while nursing a newborn. My own boss recently asked me if I thought our workload was too high. I told him that I usually managed to get out on time, even though I know many of my coworkers often stay late to finish up. A parent himself, he said, "That's because you're a mom," he observed. "The mothers in our group all know how to get their work done on time. They have to."

Uniformed service personnel are paid during their time away from work, but people on family leave are not. Perhaps we could think of ways to apply the USERRA model to maternity leave, or to any or family leave. Other countries, such as Costa Rica, are able to lump together paid maternity and sick leave in a single fund. It can be done, even in a less affluent country than ours.

Three months out of a woman's career is not that much. Three months to recover from a hip replacement, to care for a dying parent, to serve in the Reserves -- it's really not that much in the span of a person's life. Ultimately, these experiences can only help the workforce. Think of it as off-the-job training. As a human being.

A Peaceful Revolution is a blog about innovative ideas to strengthen America's families through public policies, business practices, and cultural change. Done in collaboration with MomsRising.org, read a new post at the Huffington Post each week.