Smithy, have you asked him for an explanation? IVF alone really isn't a reason to induce, so far as I know (and admitedly I'm no expert, but this comes from my OB also).

Let me tell you, forcing my body to labour at 42 weeks was *something*, I can't imagine trying to do it at 38 weeks.
I think us IVFers are so used to everything being minutely controlled and clinical, maybe it doesn't occur that things can just happen naturally sometimes.

All the best