It’s really, really hard to stick to fashion rules when you are pregnant and it’s September and it’s still so unbelievably hot outside that it might as well be July. Don’t give in and don your beat-up, tired summer maternity clothing.  There are some great transition pieces out there right now to take you through fall and then into the winter.

Ripe Maternity has released its cute, versatile short-sleeved maternity tunic in a lovely deep purple color for the fall. This tunic is actually made from a cotton/nylon blend, so it is still incredibly lightweight. But the neckline and the color work together to make sure it looks like a fall transition piece. I tried this tunic on this past winter and I was able to wear it as a dres with tights, although I am only 5′4″. If you are taller, you might need to pair it with skinny trousers.

Ripe released this tunic in charcoal and black last winter and modeled it with a long sleeved T-shirt underneath. I don’t always love the layered look when one is pregnant (I never wanted to be wearing more during my pregnancies, only less), but the T-shirt does do a nice job of dressing the tunic down and, of course, keeping you warm.

This Ripe tunic is also a much less expensive alternative to the to-die-for Isabella Oliver Maternity Jersey Pocket Tunic, pictured at right, which will cost you USD $209 here this fall. The IO Tunic is one of my all-time favorite maternity pieces–but that price is hard to justify, especially if you are on the taller side and are only going to be able to wear it as a top, rather than a dress.  Tell yourself you are getting a bargain and click here to purchase Ripe’s Jacob tunic in deep purple at Nordstrom’s for USD $89.

I blogged about this bag here when I first bought it–it turned out to have very good storage inside, particularly the discreet pocket that runs along the bottom of the bag. But the soft, supple leather was completely impractical and after one rainy day waiting on the tarmac at Heathrow airport, it was virtually destroyed. For the bargain price of USD $174, though, I do think you can justify it as your “dress-up diaper bag.” To be honest, this bag could very easily pass as your new fall satchel. No one need know it has elastic bands designed to hold bottles inside.

Click here to join Billion Dollar Babes and shop the sale if you aren’t already a member.

Not so if you are preggers. You are counting down the hours until you can get those feet, ankles and legs covered all day, everyday. It is bad enough that you have to look at your spider veins, varicose veins and swollen ankles, but having to share them with the general public is especially embarrassing.

For Fall 2010, Dutch maternity designer Noppies is mixing up the usually drab maternity tights selection with its new, cotton cableknit maternity tights. I viewed an early sample of these tights last winter in choclate brown and they are just now available online in charcoal grey at Bellydance Maternity here for USD $20. Everyday Maternity has them for sale in both chocolate brown and grey here for GBP 10.99 (USD $17). These tights will do a great job of livening up your solid-colored maternity dresses. And they will look great with the new denim maternity skirt you just treated yourself to for fall. Most importantly, they are soft, comfortable, and completely opaque. So, you and only you will know what is going on underneath your super stylish tights.

There is one small problem with this blouse–last time I blogged about it, it was priced at USD $68 and now, only 7 months later, it is suddenly priced at USD $78 in the Nordstrom maternity boutique. That annoys me. But no matter what kind of pregnant fashionista you are, you’ll need a basic white blouse for your maternity wardrobe and despite having tried just about all of them out, this one remains my top recommendation. Console yourself with the knowledge that you won’t outgrow it and have to buy yourself another white blouse in a few months.

I am usually pretty skeptical about Maternal America because their clothing is just everywhere and purchasing one of their dresses makes it very likely that the pregnant woman in the office next to yours will own the same dress. But this dress was special enough, I think it’s worth the risk. And don’t worry, it is not as short as it looks in this photo, this model must be six feet tall. It came to a very respectable knee-length when I saw the sample. Curiously, this dress is selling for USD $126 here at Euphoria Maternity, USD $124 here at Due Maternity and only USD $112 here at Chulamama Maternity.

Still, two days later, I am just as excited about the new collection, particularly because of the new winter coats IO has released. Isabella Oliver is, hands down, always the best place to buy your maternity coat. Liz Lange used to design beautiful maternity coats as well, but now that her high-end line is gone, IO is the only place to go to purchase a thoughtfully conceived, well-tailored maternity coat that will not only not make you look like you are wearing a tent, but will also last you through the season and through all of your pregnancies. Or, in my case, through numerous other people’s pregnancies, because my Isabella Oliver coats have been passed around a good bit among friends and siblings.

Every season IO comes out with at least one new must-have coat and Fall 2010 is no exception. This year, there are two new offerings, one more formal than the other. The new pieces include this classic long wool/cashmere wrap coat, which comes in three very versatile colors, camel, black and olive. It retails for a hard-to-swallow USD $445 here, which I readily acknowledge is a good bit of money for a maternity coat. If, however, you are going to be working during a winter pregnancy,  this is the nicest and most appropriate coat you are going to find. I’ve browsed through enough maternity coats at this point so I don’t even need to see the rest of the Fall collections to know that the IO coat is going to be the must-have.

If you aren’t headed into an office over the course of your pregnancy, but still need to keep warm, I would instead opt for this cute maternity duffle coat, also new this season from IO. It’s made from the same wool/cashmere blend as the wrap coat, but it’s shorter and more practical…and is a bit more reasonably priced at USD $359 here. It’s available in ivory and black. I have purchased an ivory maternity coat from IO before and though it sounds completely impractical, I was always very impressed at how well it emerged from its frequent dry cleaning visits.

Every fall, I beg readers to make the investment and buy a proper maternity coat. There are few sights as disturbing as a pregnant women jamming herself into a non-maternity coat in the doldrums of winter. The belly sticking out of the front of the coat, the buttons straining to keep the coat buttoned, the coat so tight across the top that she can’t move her arms–it is all very unsettling to see. Don’t be one of those women. If these prices are just too high and you think you can make it through the early fall without a winter coat, wait for IO to launch its sitewide sales later in the fall. They usually offer 20%-30% off sitewide closer to Thanksgiving. Also, Liz Lange for Target always releases at least one basic black maternity coat. It won’t last through more than one winter, but it usually costs less than $100 and it will get you through the cold weather just fine.

One thing, however, that the Italians have not managed to do is figure out how to sell their gorgeous maternity clothing online. Year after year, I keep waiting for them to catch on to the e-commerce thing and it is just not happening. You can sometimes find isolated pieces from the Menonove Collection (or from their other line, SARA), but never enough. I am very sorry to say that this dress is not available for purchase online, nor are the more practical pieces from the Menonove collection available online. I particularly love this floral dress, which is also part of the new collection.  And it seems like most pregnant fashionistas might get more wear out of this dress than the leather one. Click here to view all the beautiful pieces Menonove has just released for fall. But in order to make sure that leather dress ends up in your closet, you’ll have to step foot in one of the Menonove boutiques in Florence, Milan, Turino, Bologna, or Naples.