I am sorry to be the bearer of bad news, but yes, there's a very high likelihood of birth defects incl. mental health conditions. According to research studies published in 2012, the chance of severe birth defects is 5-6 times higher in children of incest, and the probability of having mild mental impairment is about 10%.
I wish I could give you better news...
Dr. Tali Shenfield
That is the primary concern with incestuous relationships.
So what do mean with that. That there going to be disabilities ?