He wants nudes but I can't because my body is in terrible shape, should I tell him?

I had two children and gained a lot of weight and it left me with a lot of stretch marks on my stomach. I've lost a lot of weight and am in good shape now but I'm left with loose skin on my stomach and also stretch marks. A guy I've been seeing asks for nudes but I always make excuses or I just cover up a small part of my stomach. But lately he's been very persistent and I don't know what to do?
He wants nudes but I can't because my body is in terrible shape, should I tell him?
Post Opinion