Just remember that the vast vast vast majority of miscarriages "caused" by amnio/ CVS are babies who were very sick e.g. the test comes back positive for one of the chromosomal abnormalities and it is impossible to say whether it was the test that caused the miscarriage or whether they would have died anyway as a result of their condition. The chances of miscarrying a child who does not go on to test as positive is much smaller.
Would knowing your child had one of the conditions change your course of action? For me it would have, but it's obviously a very personal view. I am also a planner and couldn't have gone through the rest of pregnancy with even a tiny amount of doubt. To be honest I am struggling with this pregnancy despite our results coming back really good.
Options are:
NIPT/ nifty/ harmony/ panorama test - usually privately though one or two NHS trusts are now offering this before amnio/ cvs. It is risk free and involves a scan and sample of the mothers blood. Results in 5 - 10 days. Not considered diagnostic in the UK (which is why you are given a 1 in chance rather than a yes/ no). Considered diagnostic in Australia.
Amniocentesis - invasive test, performed in hospital by NHS. Small chance of miscarriage (less than 1% for healthy babies, around 1% for those with abnormalities but also dependent on the person performing it). Results in 3 - 5 days. Available from 15 weeks gestation.
CVS - invasive test, performed in hospital by NHS. Small chance of miscarriage (less than 1% for healthy babies, around 2% for those with abnormalities but also dependent on the person performing it). The slightly higher chance of miscarriage is possibly due to the fact it can be performed earlier, when miscarriage is slightly more common anyway. Available from 11 - 13 weeks, dependent on your NHS trust. Diagnostic.
Have no test - you will likely be offered more scans to check for heart abnormalities which are more common in children with chromosomal abnormalities.