The fanciest fashions to hit the streets this fall come in an unusual size: extra-extra-extra-tiny.

Call it baby haute couture.

Though they use their feet only to suck their toes and don't think twice about spitting up on a suede jacket, more and more infants are decked out from head to toe in sophisticated duds that make the nursery look more like a pint-sized fashion runway.

"You can get tiny baby shoes from Prada, Burberry has a line of infant trench coats and dresses," Child magazine lifestyle director Kathy Henderson said. "Rather than disposable, brightly colored, cheapie things, parents are deciding they want to buy things that are keepsakes."

These days, the nicely turned infant might go cruising dressed in a cashmere sweater, weathered leather pants and the $150 JP Tod's moccasins that adorn the feet of Sylvester Stallone's and Uma Thurman's kids.

Attractive as they are, no one argues that fitting out a rapidly growing baby in a $200 or $300 outfit is practical.

"Babies don't even need to own a pair of shoes until they're walking. You can put them in socks, they don't care," Henderson said. "We've seen some baby shoes upwards of a couple of hundred dollars, which in practical terms makes no sense because the baby is going to outgrow them. But in some ways I think that people aren’t bronzing baby shoes anymore but may hold on to them."

The move toward fancy baby clothes shouldn't be a surprise. Well-heeled infants have long been a common sight in Europe, even getting their own fashion magazines. American designers came on to the scene when they realized that millions of American babies were attending play dates with barely a stitch of high-end clothing to choose from.

"It's driven by when designers get interested in kids themselves," Henderson said. "The people running these companies say, 'This is what I want and I don't see it, so I'll make it myself.'"

Stacey Zinman came up with the idea for her company, Bloom, when she couldn't find anything that was both durable and elegant to dress her baby in.

"After I had Elizabeth, there wasn't much I could find in sweaters for her that were classic and traditional," she said.

So Zinman designed 100 percent cotton sweaters in pink, blue, white and buttercup that were meant to recreate the feeling her daughter felt when she snuggled in her arms.

Now her Los Angeles-based line can be found in chic stores on both coasts, warming up celebrity babies and making occasional appearances on the CBS television comedy Baby Bob.

In a reversal, a celebrity was the genesis behind the fashions of New York-based rockstarbaby. Bon Jovi drummer Tico Torres wanted a line of clothes that would reflect the sensibility of rock musicians, bequeathing to the world babies dressed in fringed leather pants, biker jackets and "dirty" denim diaper covers.

"We see lots of cool uncles and aunts and people who don't want the usual blue onesies or frilly dresses," rockstarbaby marketing director Michele Colonna said. "Kids don't know what they're wearing. It's really fulfilling a parent's dreams."

The lines can be found across the country, with customers including Cindy Crawford and Bono, he said. Many of the non-rock star parents find themselves sartorially outclassed by their own children.

"People would go out for one less dinner a week so they can buy a nice sweater for their little angel," he said. "People now know it is essential for their child to look good."

Henderson agreed that parents would rather be plain themselves than let their children wear ratty hand-me-downs.

"Parents think, 'I wouldn't spend the money on this for myself, but I would splurge on this for my baby,'" she said.

And the trend will continue, at least until babies grow up enough to run away from the fitting room, Henderson said.

"Babies will wear these until the kid gets old enough to tell moms what they really want to wear," she said.