News of totally different on-call doctor for delivery has me weary...can I do anything?

Well you ALWAYS have a right to request a nurse or someone else be present if you're uncomfortable with the doctor you're seeing. I know my OB had a male resident working for her and when she was out of town, he had to do my exam, so I requested a nurse be present because I really don't want any man other than my husband down there. I understand how uncomfortable it is. I'm not sure about delivery though. I would definitely bring it up with your doc at your next appointment and let her know about your feelings. She should try to accomodate you as best as she can, but once you go into labor, they can't sit around waiting for a female doctor to deliver. There may not be time for that and if the only on call doc is a male, it just may have to be that way. Like I said, I'm not sure how that works, just giving my opinion. Definitely bring it up at your next appt though. Good luck and congrats on your pregnancy!