The bella band is a great way to keep your regular pants early in pregnancy. It's also a good way to cover up your stomach when it begins to poke out underneath your blouses. I purchased a small, since I am a size XS or S prepregnancy but I found it to be only useful between 12-14 weeks. Then it began to be too tight and I felt it was restricting airflow. Luckily, a friend gave me her Bella Band that was a size medium and while that may be somewhat loose on the top, works just as well holding the pants up as the small but doesn't restrict air/blood flow. So my recommendation is to go a size bigger than you normally are pre-pregnancy. You'll get more use out of that longer term. This also works great with the belly belt.