At some point in your pregnancy, you'll be too big for your normal trousers but not big enough for maternity trousers. That's where pant extenders come into play. Pant extenders work with trousers, shorts and skirts, and many women find they can get several months' worth of wear out of the products, depending on the type used. Pant extenders can also be used during the postpartum period.
The Quick Fix
The simplest pant extender can be created using a hair elastic (or a rubber band, but make sure it's a sturdy one). Loop the elastic around the button, then through the buttonhole, and back around the button again. While this is convenient, a hair elastic doesn't offer your belly much room to grow.
Button extenders consist of an elastic band with a buttonhole on one end and a button on the other, and work along similar principals as using a hair elastic or rubber band. You can find inexpensive button extenders at fabric or sewing stores, and you can also purchase button extenders designed specifically for pregnancy. Button extenders are only going to hold your trousers' button together, not the zipper, so they must be worn with a long, loose shirt or paired with a belly band for coverage.
Belt and Panel Extenders
Belt and panel extenders typically come in a kit, which will contain one or more "belts" (wide elastic bands with a buttonhole on one end, and a button on the other) and one or more panels. The panels are meant to fill in the gap left as your pregnancy progresses and your zipper becomes harder to raise. But while belt and panel extenders offer a solution to the open zipper problem, the panel is still somewhat noticeable under a short or sheer top. Belt and panel extenders often look best paired with a long, loose or layered top.
Band extenders, or belly bands, consist simply of a stretchy fabric band. Surprisingly versatile, they can support and cover unbuttoned trousers, hold up too-big maternity trousers, and even keep a third trimester belly from pushing down trousers. Bands can also serve a dual purpose, giving the appearance of a long layered tank under pre-pregnancy shirts that have become too short. Because bands are often meant to be shown, they come in a wide variety of colours and patterns. However, some women find that bands can slip down or ride up, requiring too-frequent adjustment.
During pregnancy, it's important to feel comfortable and confident in your clothes. Shop for pant extenders with an eye toward the store or site's return policy, as many may not be returnable. If the pant extender you're interested in can't be returned, it may be best to buy just one of that item so that you can be sure it works for you.