I got these to wear much later in my pregnancy. I'm normally 5'7, 140 lbs, and usually wear a size 10 in pants. That in mind, I read all the reviews that said the product measures small and bought a size large. While the large does fit my butt and hip areas, the ankles are going to need a bit of work. They're baggy. And I don't mean just a little bit loose, I mean I'm wearing baggy spandex pants. Thankfully, they're long enough that once I've sewn them, they'll fit fine.
I'm only 4 moths along, so I can't really attest to the comfort level of the full panel belly yet. I fold it down and it seems to be fine.