• Cordocentesis is also called fetal blood or
umbilical vein sampling
• This is an invasive procedure where fetal
blood from the umbilical cord is taken and tested
for suspected abnormalities
• This diagnostic test can only be carried out
between weeks 18-20 because before this time frame,
baby's blood vessels are still fragile
• Cordocentesis can be used to diagnose Down's
syndrome as a follow up to a scan
• It helps in the detection of infections such
as rubella, toxoplasmosis, herpes in the mother; a
specific analysis is performed on the proteins found
in the blood sample
• It helps detect fetal anemia, assess the hemoglobin
levels in baby's blood, and if necessary carry out
an intrauterine blood transfusion for the baby
• It is also useful in detecting rhesus antibodies
in the mother and to check if it poses a risk to baby's
well being
• In cordocentesis a thin needle is passed through
the abdomen into the uterus down to the umbilical
cord where it attaches to the placenta
• With the aid of ultrasound, a small amount
of blood is then removed from the blood vessel for
testing.
• It is a very specialized, delicate procedure
and the risk level to the baby is 1 to 2%
• Test results takes about 3-4 days
• Theoretically it is as good as any other blood
sample testing.
