Cordocentesis is a test done on the sample of fetal blood to detect any abnormalities in the fetus. The blood for this test has to be drawn from the fetus and examined. This procedure is resorted to when information from other tests like ultrasound or CVS and amniocentesis is inconclusive. With Cordocentesis specific abnormalities can be found out about chromosomes like Down's syndrome. Other problems like fetal anemia, infection or malformation of the fetus can also be established in this way.
To do a Cordocentesis test an ultrasound is first done to determine where exactly the umbilical cord is inserted in the placenta. A thin needle is guided by the ultrasound into the abdomen and then the uterine walls to the cord. The needle is then pierced into the umbilical cord to get fetal blood for a sample to conduct the tests on. This complete procedure takes around an hour to complete. Medical tests will be conducted at the laboratory and the results will be known within a 72 hour period.
Though considered a safe test there are a small percentage of Cordocentesis risks involved. This being an invasive test for diagnosis, risks involved are miscarriage in about 2% of the tests which are carried out. Other side effects are a rupture of the membranes prematurely, the fetal heart rate could drop, infection could be transferred and there could be loss of blood from the site of the puncture.
If Cordocentesis has been conducted then the mother to be should watch out for certain symptoms which should be reported to the health care provider immediately. These are amniotic fluid leak, chills and fever.
Cordocentesis during pregnancy are conducted for various reasons. It is the physician's decision entirely to conduct this test to do certain medical interventions, to make the parents aware of the condition of their child so that they can be prepared to have a child who has special needs, plan for certain changes in their lifestyle, get together various resources and support groups to help them and even to decide whether they want to go through with the pregnancy or not.
Sometimes parents may decide against such a test as they are prepared for whatever the consequences are because of certain religious and moral reasons and also because they do not want to think about terminating the pregnancy at any cost. Parents also may prefer not to endanger the life of their baby which is still being formed by carrying out such tests. The physician should give the parents all the benefits and risks involved in doing this test before carrying out such a procedure.