Bought while I was still pregnant. At 8 mo, I measured 33in. Right before delivery (38 wks) I measured 39 in. I took a chance ordering the xs because I was pretty in shape before and was pretty confident I would be able to get into it after delivery. I was able to get in it but it took laying on the hospital bed and help from my husband. It's uncomfortable to wear because you can't slouch. Mine got the weird permanent fold other people talk about, slightly annoying. But...WELL WORTH THE MONEY! My stomach melted away and I was basically pretty flat at 9 days post delivery, and I didn't even wear it 24-7 like you're supposed to. I wore it for the better portion of the day for the first 2 weeks and haven't worn it since. At 4 weeks post partum someone asked me if I had adopted my daughter :)