What happens during an amniocentesis?

Amnio step-by-step. Consent is obtained; questions are answered. Ultrasound is used to find best location for needle. Iodine is wiped on skin. Ultrasound is placed on abdomen again. Skin may or may not be numbed by injection. Amniocentesis needle (long but thin) is inserted through abdominal wall into amniotic sac. Syringe is attached; fluid is withdrawn. Heartbeat is checked. Skin is cleaned. Instructions are given.
Amniotic fluid. Initially, a sonogram is performed that facilitates locating an appropriate pocket of fluid. Then under ultrasound guidance, the needle is passed through your abdominal wall, into the uterus, and into the selected pocket of fluid. Amniotic fluid is then aspirated with a syringe to be sent for diagnostic studies. The needle is removed and the fetal well being is confirmed post procedure.