Is amniocentesis dangerous?

Patient's question:

Gender: Female
Age: 27
Can I still have an amniocentesis if I'm more than 8 months pregnant? Is it painful? What is the approximate cost?

Doctor's answer:

Generally, the best time for amniocentesis is between 18 and 22 weeks of pregnancy.
Advice:
Amniocentesis usually carries certain risks. Since you are already 8 months pregnant, the risk is even greater. If your risk is low after the Down syndrome screening, it is recommended that you do not undergo amniocentesis.