I had an amnio 3 weeks ago, following a 1:199 risk for Downs after a nuchal fold/bloods at 13 weeks.
It took us a while to decide to have it - and it was made worse by the fact the first time I went to the hospital, they couldn't do it as I have an anterior placenta and there was no space to get around it.
When I finally got it done a week later (17 wks), I was very nervous. But the procedure was absolutely fine - no worse than taking blood. I had the amnio at a large hospital, the consultant was very experienced and very reassuring, and the whole thing was over with in minutes. I was achy around the middle for a few hours afterwards, but nothing serious. I rested up for 24+ hours.
We got the all clear for Downs, Pataus and Edwards a few days later and now have all the results back and everything fine.
If something had been amiss, I'm not sure whether I could have had a termination, but I just felt that if there was a problem, I needed to know what we were dealing with.
However, now I know all is well (genetically, at least) I feel very relaxed and am looking forward to meeting DD2 !