There is a chance that her fever can be due to anesthesia as it alters the body thermostat. But you would want to rule out other potentials such as infection.

Actually, yes...epidurals or spinals can create a small, insignificant fever that is short-lived due to the inflammation that can occur with the injection locally at the site, but nothing that is sustained and/or life-threatening. That would likely point to something more systemic like a chorioaminitis infection (possibly having had her water broken for too long of a time = infection) for example.