Nursing wear, size L equivalent

I bought this at Akachan Honpo, but I only wore it once for a fitting and haven't worn it since. It's new, although the tag is missing. The size is M, but it's quite roomy for a M. I can even wear it, and I usually wear L, so I'll list it as L! The length is like a tunic, and I think it would look cute with pants.