This design by Thompson, a variation on an Arabic protection symbol, was inspired by a necklace belonging to the mom-to-be. "Protection symbols are common motifs for anything involving pregnancy or babies," Thompson says, adding that the flames symbolize strength, protection and purification.

This belly painting was the first for Greenawalt, who has a day job as an electrical engineer. These days, he no longer has models go topless. "The belly paintings are so sweet, nice, and happy that I just don't feel like the nudity plays well," he says. Greenawalt often creates designs inspired by the baby's bedroom decor.

This model requested a baseball theme in honor of the baby boy she was carrying. "Painting the belly to look like a ball works really well," says Greenawalt. He painted this design at his home as the father looked on, and snapped this photo at home plate on a local baseball diamond.

This design by New York-based artist RoByn Thompson incorporates the Zodiac symbols of the mother, the father, and their baby. Belly painting is growing more popular as a baby shower activity, Thompson says.

For this mother-to-be, Thompson created a design based on Cowrie shells. "They're goddess symbols, and fertility symbols," she says. Coming up with the design is a collaborative process based on emails and phone calls with her clients, Thompson says. Her one-of-a-kind paintings start at $200.

Phoenix-based artist Mark Greenawalt created this painting in front of a live audience as part of a jellyfish-themed gallery exhibition in Phoenix.