I didn't have it done with Izzy, and I worried all the way to my 20 week scan off and on about it. I m/c at 12 weeks before I had her so I always stress during pg and I don't know that I would terminate however this time around I didn't want the stress that I had with Izzy and not knowing if that makes sense. Although I had a whole new lot of stress waiting to have the appointment, getting my scan results and waiting for my blood/combined results. In hindsight I probably had just as much stress but in a lesser amount of time. Fortunately our results came back with very low risk, 1 in 11,500 for downs, and 1 in 65,000 for Trisomy 18. As the other posters have said, I guess you need to decide that if you do the stress and results may still not be conclusive and will that just make your stress and worry even higher? It's a tricky one hun - good luck deciding.