I bought a pair of smart maternity trousers from Gap for work, the only downside is the bump band is more like spanx material than the usual stretchy jersey that you get on most clothes.
At 22 weeks they're getting tight; less on the bump bit, but more on the elastic that holds them up at the top (if that makes sense) I think I should be able to add extra elastic in to the waistband, but i can't figure out where to make an incision to do this (probably at the back as that's where the seam is) and whether it's worthwhile trying to sew elastic to existing elastic expand it, or just replace the whole thing.
My sewing skills aren't too bad, but I need help in figuring this out before I destroy the whole bump band by mistake!