My husband always calmed my nerves by telling me there were crack babies and all sorts of drug babies out their and mine wasn't so the odds were even greater for survival . Also if you miscarry early on it is more likely a developmental issue I always say rejection is gods protection . You don't want your baby coming out with one eye, kidney, and half its intestines (exaggeration) have faith that God is molding your Presious one to be its best, and if crack baby's make it so will yours...as hubby would say.
Distraction. That's what I had to do. With my daughter I didn't find out until 22 weeks so ai didn't have that fear or have to wait the whole 9 months. This time I found out at 4 weeks 5 days. So distraction really helped me. I am now 16 weeks 5 days and still do that at times.
Just try and think baby is fine. Try not to worry as its not healthy for baby. The calmer you are the better it will be:) think positive!!!