What can I expect with pyelonephritis during birth?

Antibiotic treatment. Your infection will be treated with antibiotics and your baby will be observed for signs of infection.
Depends. Hopefully you mean you had pyelonephritis earlier in pregnancy. If so, it should have no impact at all during delivery. It is a kidney infection treated with antibiotics. Once it has resolved then no special treatments or precautions need to be done during the actual delivery. If you are in labor now with a current kidney infection then antibiotics will need to be continued.