An amniocentesis may be carried out in the case of- 

• Down Syndrome
• Sickle cell anemia
• Cystic fibrosis
• Muscular dystrophy
• Tay Sach’s disease
• Abnormal screening tests
• Rh disease

Before beginning an Amniocentesis, an ultrasound is performed in order to check the position of the fetus and placenta, the heart rate of the fetus and to find a suitable spot to inject the amniotic sac. A long needle is inserted at the identified place and an appropriate amount of amniotic fluid is withdrawn. The amniotic fluid removed is then sent to a lab for testing. 

There are several risks involved in an Amniocentesis. There may be an infection or bleeding at the site of insertion of the needle. During performing the test, there are chances of the amniotic fluid to leak out of the vagina. If done in the second trimester of the pregnancy, there are also possibilities of miscarriage. During amniocentesis, there may be a needle injury which may harm the fetus. The baby’s blood cells may enter the mother’s blood while carrying out this procedure. In case the mother has HIV or infections like Hepatitis C, the infection may spread to the baby while carrying out an Amniocentesis. 

• Fever 
• Bleeding or leaking of amniotic fluid after the Amniocentesis
• Severe pain and cramps
• Changes in movement of the fetus