The point I'm making is it's fine if you're smart and sanitary.
Any animal droppings are to be avoided as well as simply handling reptiles. Although, I have snakes, geckos, cats, and rats. I still handle them and change the poop but I wear gloves and clean myself up well before touching anything else. Even though they are all indoor animals I like to be clean to be safe.
Actually, you can clean catboxes when pregnant, you just should do it often. The concern there is toxoplasmosis, which (IF the cat has toxoplasmosis, which most cats don't) can be spread to a human if the human comes into direct contact with the cat's feces (not urine) IF the feces are more than three days old and IF you then manage to get some fecal material into your mouth. (Not very easy to get toxoplasmosis that way, is it? lol)
As far as rabbits go, if the rabbit is an indoor animal he is not at risk for toxoplasmosis (and frankly, I don't even know if a rabbit could get toxoplasmosis if he did go outside). Just use regular hygiene if you handle the poop or pee of any animal, wear gloves and wash your hands afterwards.
If toxoplasmosis is a concern, always wear gloves when gardening (the microorganism that spreads it lives in the ground) and also avoid raw meat.
Just make sure to wash your hands well afterwards. It would probably be best to have someone else to do it but if there is no one else just be extra careful!
I dont know for sure, but its probably not a good idea!