Amniocentesis is a diagnostic test performed during pregnancy where a small sample of amniotic fluid is taken from the uterus. This sample contains cells from the fetus and it is analyzed in the laboratory. 

Your doctor may prescribe amniocentesis in the following instances:

• If the fetus has higher than normal risk of Down syndrome.
• If any of the expectant couples’ previous baby is affected with a genetic disorder.
• If the couple or one or more of their relatives are either affected with a genetic disorder or are carriers of genetic disorders such as Thalassemia, Sickle cell anemia etc.
• To check if the fetus has an infection.

After the procedure, one can rest for about half an hour and can resume activities.