And now, reports The Early Show's Debbye Turner, many wives of those soldiers, and many GIs themselves, are pregnant.
In November alone, the base expects close to 200 babies to be delivered at its hospital.
And that's just the beginning: The high rate of births will continue into April, with the post projecting more than 1,000 births over the next six months, 70 percent more than usual.
Col. Matrice Browne, chief of women's health at Blanchfield Army Community Hospital at Fort Campbell, isn't surprised: "When folks go away for a while, they come back. And it's a perfect time for them to expand their families."
Twenty percent of Fort Campbell' s pregnant women are active duty soldiers. If healthy after the births, these new moms can be deployed as early as four months later.
These women are expected to continue their army routine during their pregnancy, including staying physically fit. The fort offers an exercise and education program for the pregnant soldiers that begins when their prenatal care does. It's called STARS, which stands for Soldiers, Training, Ability, Readiness, Spirit.
The maternity ward's just-completed $4.2 million renovation, planned before the boom, comes just in time.
Fort Campbell was also hit with a spike in births a decade ago when soldiers returned from Operation Desert Storm, Turner notes.
The latest boom is being dubbed Operation Baby Freedom, in honor of soldiers returning from Operation Iraqi Freedom.
Sgt. Carl Schimpf's wife, Samantha, says the baby they're expecting was conceived shortly after his tour of duty in Iraq ended. "A couple of weeks after he got back, he got 30 days leave, and we took a trip to Disney World. ...And on the way home, I suspected, I think I might be pregnant."
She was, and they're expecting their second child, a girl, in November, 10 months after Carl got back.
Carl missed much of Samantha's first pregnancy, so, "I'm looking forward to all of it, you know. Being able to hold a baby again, and to feed her, and to just be able to talk to her. And you know, just look at her."
But the happy times are tempered with the realities of war. Says Carl, "It's on the back of your mind. You know, when I'm going to go next, where I'm going to be. But if you start thinking like that all the time, then ... you don't enjoy the time when you're here."