Does having a Feliway Comfort Zone diffuser in the house pose a risk to an unborn or newborn baby?

no it is safe

Feliway Comfort Zone Diffuser

No, Feliway won't harm a fetus or a newborn. You could also have SoftPaws put on to prevent damage to the carpet while you're working with him. That way you wouldn't have to spray him to prevent damage. It's always best to redirect them through positive reinforcement of good behavior where possible. Be sure he has plenty of appropriate scratching surfaces available, both horizontal and vertical. Most cats really like the corrugated cardboard scratchers and the bonus is that they're very inexpensive. Put one in the area where he's scratching the carpet and be sure to praise him (maybe even offer a treat) when he uses it. If he tries to scratch the carpet, pick him up gently, tell him no and move him to one of "his" scratchers. Again, praise him when he uses it. If you're raising your voice, yelling or disciplining him physically when he misbehaves, please stop immediately as this can only add to stress and is not effective with most cats. While it's true that cats recognize hormonal changes that we go through during pregnancy, I'm hesitent to believe that this is the root cause of your cat's stress/behavior. There has to be some other trigger that's setting him off. It could be that there are other cats in the neighborhood that he's seeing or hearing on his property... even if he's indoor only. It could also be changes in his routine or environment. Try to keep all these things as consistent as possible. Sometimes Feliway just isn't enough to calm a really stressed cat. If that doesn't work for you, talk to your vet about putting him on an anti anxiety medication short term. Both Amitriptyline and Valium have shown to be very effective in reducing anxiety and helping with stress related behaviors in cats. One of mine has a whole new lease on a better life now thanks to Amitriptyline.

More on SoftPaws:

http://www.softpaws.com/

As long as you keep a close eye it should be ok. If you change the litter box make sure you or anyone who touches the litter washes their hands afterward. If your baby sleeps in a room that the cat has access to, you need to get a bassinet screen to keep the cat away from the baby while he/she is sleeping. Kittens like warmth and will cuddle up to the baby and there is a chance it could accidentaly smother the baby. Animals are great to have around children, but always remember that they are animals, and you have to keep a close eye at all times with babies and children. EDIT: we have a 7 year old Rat Terrier and a 1 year old Rottweiler/Black Lab mix. They pretty much ignore the baby, but we still always keep a close eye when the dogs are in the house, or we are outside with the dogs.

Shouldn't, the diffuser is made up of the hormones released by the glands on the cheek and between the toes in cats. It's a pheromone, the feel-good hormone in cats. If the diffuser does cause harm than having a cat would cause harm as well. To the best of my knowledge it does not.

You can contact the company just to be sure:

http://www.feliway.com/us/Contact-Us