Amniocentesis is a prenatal diagnostic procedure. There are specific medical reasons to consider this procedure. According to the American College of Obstetrics and Gynecology (ACOG) the new recommendations state that all women regardless of age may have the option of amniocentesis. It is typically done between 16 and 20 weeks. It involves removing the fluid from the sac of the fetus. This fluid contains cells that are shed from the fetus. For most diagnosis the cells have to be cultured for a period of time before the analysis is done. The standard tests on the fluid are for the chromosomes (this looks at the total number of chromosomes, pieces missing or rearranged). Therefore Down syndrome is just one of the chromosomal abnormalities evaluated. Also, Alpha-fetoprotein (AFP) is measured to diagnose open spinal lesions. I am also working with Biocell Center that would give you the opportunity to save a small amount of amniotic fluid for stem cells. Please refer to the link for further information or please call the office.


An ultrasound is done to evaluate the fetal anatomy, the weeks of pregnancy and the location of the placenta and amniotic fluid. Then the location to insert the needle through the abdominal wall is determined. The skin is cleaned with betadine (unless there is an allergy to Iodine), local anesthetic is injected into the skin (unless allergic to lidocaine or you decline the anesthetic.)Under ultrasound guidance the needle is inserted through the skin and the uterus into the sac of fluid. A small amount of amniotic fluid is removed. The thickness of the needle is thinner than the needles used to draw blood from you. The fluid is then sent to the lab for chromosomes and protein analysis. The fetal heartbeat is then shown to you. If your blood type is Rh NEGATIVE then you will receive an injection to prevent you from forming antibodies against the blood of the fetus.


Occasionally you may have some cramping, slight bleeding or fluid leakage. A majority of women have no complications. There is a procedure pregnancy loss rate of 1 in 300-500. It is recommended that you rest the day of the procedure and for the next 24 hours you do not lift more than 10 pounds, exercise or have intercourse.


Typically it takes 7-10 days for the results. It may take longer of other tests are done or if the cells are growing slower than usual. One may get preliminary results in 1-2 days with special type of testing. The genetic counselor can give you more information regarding this option. Most insurance companies do not cover the testing done for preliminary results.

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