Honestly, I think if they look hard enough they will find a link with anything and Autism.
My eldest son is Autistic and I did NOT have GD. I have even read an article that having a syntocin drip during an induction is also linked to an increased risk of ASD in that child and that if someone in your immediate family has an autoimmune disorder, you also have an increased risk.
To be honest, i adore my son, he is hard work but i would never swap him for all the world....he makes us better people for being around him.
I wish you all the best for the rest of your pregnancy