Ignore him, he sounds a total wally! Walking is excellent in pregnancy as it encourages your baby to get in the head down position.
If you have a well-behaved dog, there is no reason you shouldnt walk her.
I dont walk my dog on a lead, as he is very boisterous, pulls really badly, and has pulled me over a few times now (even though he's only a Jack Russell, he is VERY strong). If he is just going round the park, my hubby takes him, whereas I take him in the car up Loch Fitty, where there are hardly ever any other dogs, and I let him have a damn good run, while I walk at my own pace after him!