The change of the seasons means it will soon be time to don those sweaters and cardigans, pick out some stylish boots and sport jackets and full-sleeve tops. When you're pregnant over the fall season, it can be hard to figure out how to put together a stylish but functional ensemble that will keep you comfortable as the temperature changes. The secret to looking great this season? It's all about the layers.

Layering your look is a simple way to wear your favorite pieces all year long and create a fresh new look each day. When you're pregnant, you also need to think about staying cool and comfortable when those hormones start to get the best of you. Fall is a great time to layer clothes such as tank tops, short-sleeve tees and button-down blouses with some fresh new pieces such as vests, cable-knit sweaters and long cardigans.

Just make sure you're picking up each piece from the maternity department so you are accommodating for your growing figure. Some of the best layered combinations for the mom-to-be this fall include:

Long chunky-knit cardigans with maternity leggings and a short-sleeve top
Wide-leg corduroy pants with a wraparound top and a long sweater
Dark brown khaki pants with a smock tank top and a long, full-sleeve cardigan
Bootcut jeans with a long v-neck tunic top and contrasting tank underneath
Knit trapeze top with twill pants and topped with a chunky sweater

When you're just lounging at home and need to wear something comfortable during those especially painful or bloated days, stick with the ¾ sleeve baby doll tops, short sleeve faux wrap tops and sleeveless baby doll tops paired with some yoga-style capris or wide-leg pants, and wear a long sweater or cardigan over it if you get cold.

Just remember: even though it's the fall season, your body may not be responding to the actual temperatures outdoors on any given day. If you're feeling especially hot in the middle of October, or feeling chills in early September, adjust your ensemble for the day by layering light and heavy clothing so you can be comfortable all day long.

By month #4 of your pregnancy, that baby bump is going to be the center of attention as you go about your day. During this trimester, you'll need some comfortable clothes that expands with your growing baby, and this is especially important for your weekend wardrobe that typically includes jeans, khakis, crop pants and loose-fitting tees. Some moms-to-be can't wait for the weekend when they can throw on their super-comfortable jeans and tees, but you'll need to buy some maternity versions of your favorites for pregnancy. Here's what you'll need for the weekend/super-casual wardrobe during your term:

1. Maternity jeans. As you start to get bigger around the middle, you'll need a flattering cut of denim jeans to wear with your casual tees and tops. Maternity jeans with an adjustable waistband are important, but you'll also need to pay attention to the cut of the leg. Stick with jeans in the flare or bootleg style because these will elongate your figure and balance out your shape better than 'skinny jeans' and tapered legs.

2. Stretchy tees. Forget the super-fitted tees that you used to wear on weekends after your gym routine. When you're pregnant, you'll need t-shirts that have Lycra and other stretchy fibers mixed into the cotton. Look for tees made with Lycra and double layers, because these will provide the extra support that you need.

3. Drawstring pants. If you prefer to lounge in pants and baggy tees instead of jeans on the weekends, invest in a quality pair of drawstring pants. These naturally adjust to your waistline, and you can relax with ease with the wide-leg fit and loose cuts. Just avoid buying these types of pants that are a few sizes too large, or you risk looking like you're wearing pajama bottoms.

In addition to the clothing essentials, you'll need a comfy pair of shoes for your weekend errands and activities. Make sure you get fitted for some soft-soled or rubber shoes so that you get plenty of support all day long. Swollen ankles and feet will feel much better in a pair of shoes made with breathable, stretchable material.

Staying stylish during the dog days of summer when you're expecting can be challenging, especially if you're in your third trimester and are experiencing the aches and pains of pregnancy. It's very important for the mom-to-be to stay cool and relaxed under the summer sun, so choosing the right type of clothing is a top priority. Since you want to be stylish too, here are some of the best clothes to add to your summer collection:

1. The maxi dress. Super soft and lightweight materials make the maxi-dress a definite yes for the season. You can relax in these long, loose, flowing dresses designed with tropical prints or a Grecian-inspired cut for a romantic look. Add a pair of gladiator flats or kitten-heel sandals for a complete ensemble.

2. Maternity capris. 'Tis the season to show off those gams, so don't hide in drawstring pants or jeans this summer! Wear some capris for casual days at the office and weekends, so you can work up a tan on those legs. Maternity capris made with stretch material are comfortable and stylish.

3. Relaxed button-down shirts. Loose and flowing clothing is the best match for a mom-to-be, especially on days when you're feeling bloated and tired. A loose-fitting button-down shirt will help you stay relaxed and comfortable all day long. Choose a light-colored shirt to help you beat the heat this season, without compromising on style.

4. Loose skirts. This season's frock-style skirt trend is at the top of the must-have list, which makes it a necessary addition to your maternity wardrobe. These ultra-feminine and playful skirts are a great way to show off your baby bump in style!

5. Peasant tops. Catch the Bohemian wave this season and enjoy a splash of color with a peasant top. Maternity peasant tops and blouses are designed with extra fabric and tend to flare out at the waist and sleeves. This is a great cut for moms-to-be, and can be especially flattering if you've gained some weight.

Staying cool and comfortable in the heat can be a challenge in itself, and you can multiply the effects of the heat by ten when you're pregnant. Pick up any of these stylish summer must-haves so you can enjoy the best of the season!