If your belly is growing and the button on your jeans is popping, it's time to build your maternity wardrobe! But, that doesn't necessarily mean you need to go buy a bunch of new clothes, and it certainly doesn't mean you need to rely only on specialty shops. Your maternity clothes are probably already in your closet.

You'll want to build a set of looks that flatter your new shape. You don't have to look frumpy! When your body begins to change, the rules of style change along with it. Whether or not your clothing hugs your bump or flows over your belly to hide it a bit, you want your maternity outfits to balance your round middle by emphasizing the long and narrow parts of your body. Think long legs and empire waists. Don't forget that comfort is key! Here are some items that will look and feel great on a mom-to-be's growing body!

Soft cotton fitted T's and tanks are perfect for layering, or they can be worn alone. Try to buy the softest cotton you can find with 2% spandex, it really makes a difference for your comfort during pregnancy. The tops should be fitted, but not constricting. You also want them to be on the longer side. Another piece for layering is the cardigan. You have lots of choices here--cotton or cashmere, longer and looser or cropped and fitted.

Pull-over sweaters are your go-to for staying cozy, especially on chillier days. Cashmere is best, because of its softness. A sweater should hit at least an inch below your belly button, and a tank under it should reach your hips if the sweater doesn't. Short sweater dresses you already own are perfect. Avoid wearing those you want to wear them again post-pregnancy as dresses though, they will stretch out.

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Tunics are the perfect way to dress up your maternity outfit and have fun with your style. A tunic is a loose and flowing long top. When your belly gets round, many of your short dresses can become tunics! The styles that work for maternity looks are wrap dresses and empire waists. For a sheath or Aline, slim down your look by using a skinny belt above your bump. Cardigans can be layered over tunics, and for a spaghetti strap tunic, a fitted-T looks cute under. Avoid wearing a chunky sweater over a tunic. They pair best balanced with leggings, you can add a pair of wedges for a chic look.

Fitted maxi-dresses are a very cute way to show off your bump. Pair with a cropped denim jacket and flat, strappy sandals. Leggings are your friend! High-waisted yoga leggings are versatile and comfortable and they pair well with almost everything.

The shoes make the outfit. Black leather riding boots help dress up an otherwise casual outfit. Plus, they pair perfectly with black leggings. They're flat, which is preferred while you're pregnant, but they still give you a lean, stylish look, and help emphasize your legs to balance your bump. The most slimming height should hit at the widest part of your calf and below your knee.

You can build a maternity wardrobe that you'll look and feel great in without spending a ton of money! Have fun with your look, and try to repurpose some of the things that you already own!

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