I'm making a "newborn" size that's just 37x37 or so. It's for my almost-here grandson and I can only imagine I will make a new-size quilt for every "new size" he becomes! For now, his momma is most concerned with it matching the nursery. Later she won't care.

I made my first one 30" by 40" I think, and I've done some 36" by 48", and several about 36 by 36.

I don't think babies outgrow quilts so fast. My son is three and still uses the 36" by 36" one I gave him. Granted, in the winter it isn't enough, but right now, it's the only thing on his bed becuase it's more of a comfort item. But of course I made it for him, and I'm a quilter. So maybe non-quilting mamas would see it as "outgrown" already.

I do like to make baby quilts that are bright colors, so when they are older they can still have it across the foot of their bed, and it won't look like a "baby" quilt.

I like to make mine 56 x 56 because I like them to be used longer than 6 months, so much time and love goes into each quilt, never mind the expense. Most new mothers receive lots of receiving blankets and store-bought blankets(quilts) for their newborn. Mine will usually fit a toddler bed or single bed. They make great blankets to let the baby/toddler lay or play. If you go to search and type in Just a few of my quilts, you will see two examples of my baby quilts for co-workers.

For my baby quilts, i do not go wider than WOF. usually 40 x 40. just me. I don't want to piece a back for a baby quilt.