I had a 125 Vespa, not quite a powerful motorbike but quite nippy all the same...had an accident in Nov '10, not my fault, it was a car pulling out of a side street who wasn't paying attention
and unbeknown to me, I was pregnant at the time! I was lucky. I just sold my Vespa a matter of weeks ago there as it kinda shook me up that I'd had the accident whilst pregnant, and I couldn't bring myself to ride it.
However, a friend who was pregnant used to go on the back of my OHs Suzuki 1000 when we all went out for a ride. Her OH was just learning to ride so couldn't take a pavillion rider and she was fine and her DS is near 2 now.
It just depends on how comfortable you feel being a pavillion rider whilst pregnant. You may need to make more loo stops than the norm
I won't get on the back of my OHs Suzuki as...and this is most likely the daftest reason ever, but I can't shake it...I'm scared that the vibration of the bike will cause baby to vibrate causing problems...plus with my belly now, there is zero mission of me swinging my leg up and over
If you're worried, I'd have a chat with your MW or GP and see what they'd recommend. If you decide that you don't wana take the bike, can you change the ferry booking and take a car instead? Not as much fun though eh? I miss my two wheels!
Hope you enjoy your hols whatever you decide. x