If it helps the risk of miscarriage following an amniocentesis is around 1 in 200.
Many people find this helpful in that if the risk that something going wrong to a baby who is actually healthy outweighs the risk that there is something wrong they don't proceed. However it really depends on how important it is to you to know. If you really need to know for your mental well being and for a happy healthy pregnancy then it is something you should consider.
Even though the numbers suggest that there is 382 out od 383 chances your baby is absolutley fine you need to think about what you if you were the one, if you would keep going with the pregnancy anyhow, then that risk is too high...IYKWIM
Hope that helps