Are you considering getting an iguana, or do you already have one and are thinking about getting rid because of the perceived risks?
I would never advise getting an iguana as a pet unless you have a huge amount of space to dedicate to its enclosure, and a huge amount of time to dedicate to its taming and handling... and then only if you are fully aware of and happy to take on the big long term commitment of keeping these wonderful creatures.
Sadly the huge numbers that are dumped on rescue centres shows that most people who buy are not...
Getting one when you have very young children would not be wise timing at all, imho. If, however, you already have one and are debating whether or not to keep him/her, I do not see any good reason why you should get rid. IF properly managed - both hygiene and safety wise (as a free roaming ig could obviously do serious damage to an infant, as well as spreading bacteria) then yes you can certainly still keep reptiles while you have young kids.