I want to get a kitten..

Okay so we’re moving soon to a place where I can finally have a cat!! But I’m 5 weeks pregnant... my partner will change the litter box everyday but because we’re looking to adopt from the animal shelter is there a chance where toxins could still be in the poop? And my partner made a big deal about the cat stealing the baby’s breathe after it gets here but that’s just an old wives tale right?