Yes, your child is at risk of suffering from Downs Syndrome. Down Syndrome is a genetic disorder in which an Extra Chromosome 21 is transferred to the child which may lead to this disorder. In short you are at the greater chances of having a Mentally Retarded Child.
The risk to Trisomy 21
increases with the increasing mother's age.
This is due to Nondisjunction of Chromosome no. 21 while formation of baby takes place. Every one of us have 46 Chromosomes 1/2 of them comes from mother and other half from father. In this case one extra chromosome comes. And total chromosomes number becomes 47 instead of 46.
The test done upon you are of Biochemical Origin which doesnot give the confirmative diagnosis however, we can't even ignore to them. Hence, Obstetricians Draw some Amniotic Fluid
from the sac in which baby is growing. As these are the baby's own cells. We geneticist perform a test called Karyotyping for it.
For Culture process of Amniotic Fluid it takes 10 to 15 days hence again one has to wait till the result comes. But these results are confirmatory whether your child is going to suffer or not.
Your Obstetrician is in hurry as in India Legal Procedures does not allows for late Medical Termination of Pregnancy
if been needed by you.
You are already having 4 children, so will you be able to accept such a special child does the family is going to except the child? etc. are questions which you and your family has to decide and for that you should get and enough time to think upon it.
So, its better to go with your Obstetricians opinion and you should see a geneticist immediately.