Black-Tie Style for Moms-to-Be

When it comes to duplicating the pregnant black-tie style of Hollywood celebrities, it's all about the silhouette and not the brand name, says Amy Tara Koch, style trend reporter for The New York Times, DailyCandy and The Huffington Post and author of Bump It Up: Transform Your Pregnancy Into the Ultimate Style Statement. Whether you're three months or 39 weeks along, Koch shares some of her how-to points for looking glam, gorgeous and party ready.

Draping is everything when it comes to pregnant black-tie attire, and in her purple Oscar gown, Natalie Portman dazzled. "What she's wearing is so flattering because it flows over her bump, it's ruched and it's not super clingy," says Koch, who suggests drawing attention to your neck and decolletage when pregnant for a thinner appearance."[Portman's] dress is also quasi-empire cut, which gives the illusion of the waist."

Claire Danes' sleeveless, marigold yellow dress with a drop waist is exactly the sort of style to wear when you want to stand apart from all the other pregnant moms. "The color was such a stand-out, look-at-me kind of color for the red carpet," says Koch, who notes that this is also the type of dress you can wear after you have your baby. "It just worked with her coloring so well. And the blouson type of style of the dress draped perfectly over her bump."

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At the premiere for her film The Eye, Jessica Alba was decked out in a floor-length, white strapless dress with silver embellishments. "Embellishments on the top strapless portion of the dress make it the focal point, so you don't have to wear a necklace," Koch says. For added glamour, a pair of long, neck-grazing earrings elongates the neck—where you rarely gain weight when pregnant.

To look ever-posh at the royal wedding of Prince William and Duchess Kate, Victoria Beckham donned a black tunic mini-dress with a classic boat neck and asymmetrical hemline that works brilliantly for pregnant women who want to give their gams the spotlight. "It's shorter at the knee and long in the back, which gives it an edge and helps a woman to look taller," Koch says. Only caveat: "You have got to wear high heels." Oh, and skip the hat.

At this year's Screen Actors Guild Awards, expectant mom Busy Philipps looked sensational in a form-fitting, long-sleeve black evening gown made of stretch jersey fabric. "Go with a version with a lower neckline and wear long earrings and your hair down," advises Koch. "If you want to flaunt your baby bump, this is the dress you do it in."

"Nicole Richie does the bohemian formal wear to perfection," Koch says of the celebrity mom of two. "When you're pregnant, this is such a great look. Pick a halter dress that's long and flow-y, and always wear your hair down or with a beautiful headband." Eye-catching earrings and layers of chunky necklaces give this look a glamorous '70s vibe, Koch says.

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When celebrity stylist and fashion designer Rachel Zoe did pregnancy, there was never a moment when she didn't look chic, especially when it came to swanky black-tie soirees. "For one event she wore a black silk tunic gown with fabric draping over one shoulder," says Koch, who recommends the tunic as a sexy yet more forgiving alternative to any clingy-type dress. "Big chunky jewelry looks great with a tunic dress and keeps it all in proportion."

Artistic accents on an otherwise simple dress can turn something basic into something that is breathtakingly beautiful, Koch says. "When Reese Witherspoon was pregnant with her third child, she wore this gorgeous dress to the White House that was stretch jersey material and had knotting detail on top," Koch says. "The artistic detail elevated the dress from basic black to red-carpet ready." A pair of turquoise earrings add a pop of bright color.