Congratulations! My step son is diagnosed with severe autism and failure to thrive. So he didn't really understand the whole pregnancy thing... While pregnant with my now 2 year old as I started getting bigger and the baby started moving around more and kicking, I would put my step son's hands on my tummy and boy did it freak him out! Lol! I'd tell him "baby" and he'd look at me all funny... So my husband and I took him with us to a do a 3-D sonogram, it was wonderful... He saw the big belly, the sono tool on my belly and his baby brother on big screen. He repeated back "BABY!!!" So everytime when we'd do something like set up the nursery or buy baby stuff I would ask him what does he think his baby brother would like and he'd put whatever it was in the cart and the he would put it up in nursery. When his baby brother came home he was very excited... Just kept a close watch on the boys as my wonderful step son doesn't know his own strength and loves to hug extra tight. Now I can't separate the two of them. Yes they'll fight over toys, make huge messes together, lock momma outside in the back yard when chasing after the dog to get back into the house (grr) and laugh at her through the windows...They are the best of brothers and friends! :)

Congrats. I would not worry about that at the moment and focus on the pregnancy. Keep stress low which is hard to do. I would recommend taking methyl folate or folinic acid daily (bioactive form of folic acid) rather than cheap synthetic folic acid during the pregnancy as well as 5000iU vit D daily. Both of these are known risk factors correlating to ASD. And avoid any flu shot during pregnancy. Good luck.

Thank you!