Brief Answer:
Amniocentesis should be done

Detailed Answer:
Hi dear,
I have gone through your question and understand your concerns.
I have reviewed the triple test serum screening report.
If the risk of trisomy 21 or Down syndrome is found high in the serum screening, then the next step is to confirm the diagnosis by doing amniocentesis and getting the exact karyotype or chromosomal pattern of the fetus.
Moreover her age of 42 years also warrant amniocentesis as the risk of trisomy 21 increases with the increasing age of the mother.
Amniocentesis is obtaining some amniotic fluid by putting a syringe in the uterus around fetus and getting the chromosomal analysis of the fetus done.
Amniocentesis is preferably done between 16-20 weeks of gestation.
It can be done at any fetal medicine center.
Further decision is to be taken based on its result.
Hope you found the answer helpful.
Regards
Dr Deepti Verma
OBGYN
Maternal and fetal medicine specialist

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