Amniocentesis

Genetic Screenings (AFP, Prenatal Risk Profile/Triple Screen, and Ultrasounds) seek to discern which pregnancies carry an increased risk of fetal abnormalities; it does NOT tell you which babies have abnormalities.  Because of this, there can be false positives in the screening process which can be quite emotionally alarming to the parents if they don't understand this;  the final word on whether your baby possesses the abnormality he/she is at risk for, often won't come until his/her birthday--which leaves many parents on edge for much of the nine months.  Most women who do receive a "positive"   in one of these tests  (indicating increased risk of a fetal abnormality),  however,  go on to deliver a perfectly healthy baby.  If you decide to participate in the genetic screening for whatever reason, and the results come back "abnormal", your provider will more than likely recommend further testing.

Diagnostic Tests (Chorionic Villus Sampling and Amniocentesis) can give you more accurate results, though the risks for the baby are much higher with these invasive tests.

Genetic screening, as with any test/procedure done during pregnancy, is entirely optional.  You may choose to decline for any reason.  In deciding whether or not a particular genetic screening is right for you and your baby,  you will want to consider:

• the benefits of the test--detection of abnormalities such as Downs Syndrome, spina bifida, etc. 

• the risks of the test--ranging from stress--sometimes undue--on the parents to loss of the baby (miscarriages can and do happen with many of these tests because of the test invasiveness--even to those babies who were otherwise perfectly healthy and thriving before the test)

• acceptable courses of action for your family--it is often said that if an abortion is not an option for you, than genetic screening will not make any difference--other than possible limited preparation for the handicapped child

• family history of genetic disorders

Amniocentesis is a procedure recommended to mother's for screening of neural tube defects (spina bifida, anencephaly, etc.) and some genetic abnormalities (Down syndrome).  Amniocentesis can also reveal the sex of the baby, to screen for gender related disorders.  Because this uses a sampling of the amniotic fluid, this test must be done after 14 weeks as there is not sufficient fluid before this time.  The optimal time to have this procedure is 14-16 weeks.

After the mother is given a local anesthetic, a small hollow needle is inserted through the her abdomen, into her uterus.  (Ultrasound is used to guide the needle away from the baby.)  About 1/2 ounce of amniotic fluid is drawn out.  The amniotic fluid, which is swallowed by the baby and then excreted through the baby's bladder,  is then analyzed. 

Risks to the baby from  the amniocentesis are higher than many tests because of the invasiveness of this procedure.  Risks can include infection, rupture of membranes, puncture of the placenta or even baby, and miscarriage.  It is estimated that about 2% of babies will be lost/miscarried as a result of this procedure.