I do appreciate your concerns. AFP levels alone are not indicative of Down Syndrome. You will need other tests
(blood estrogen and HCG levels) and ultrasound to confirm or refute the suspicion. In Downs Syndrome, AFP and
estrogen are low and HCG is very high (triple test). Amniocentesis is done in highly suspicious cases.
The alpha-fetoprotein or AFP and estriol levels are low in a Down syndrome pregnancy, so their levels would be
below the average (less than 1.0 Multiples of the Median [MOM]). The hCG in a Down syndrome pregnancy would be
greater than 1.0 MoM. These results are then correlated with fetal age on ultrasound. Then the results are
correlated with maternal age. If all the components are greater than 1.0 MoM (another way of interpreting the
results of this triple test is taking a cut off at 1/270), and woman is younger than 25 years, then risk is
comparatively low. But in a woman 30 years or above, the risk is pretty high. On Ultrasound, collection of
fluid at the back of the fetal neck, called nuchal transluceny is taken as a high level risk factor for Down
syndrome. Soft markers on ultrasound indicate a probability of Downs syndrome in the fetus. These markers are
just indicators and not confirmed diagnosis of Downs, which can be achieved only through amniocentesis. An
echogenic intracardiac focus however is considered a high level marker and shows increased probability. CPC is
a mid level marker and the two together show a good chance that baby has Down. This should be followed up with
amniocentesis. Having said all this-the combined results can only predict the risk-it does not say that fetus
has Downs Syndrome. For confirmation amniocentesis will have to be done.
Since you are 36 years old, the triple test and ultrasounds should be done to assess risk, followed up with
amniocentesis if need be. Please discuss with your doctor. Please feel free to ask anything else you may want
to know. Take care!