A 35 year old female with a previous history of bih of a child with Down's syndrome, presents with 18 weeks Amenorrhoea. The Investigation of choice rule out Down's syndrome in the present pregnancy is:
The Answer is B (Amniocentesis) : At 18 weeks of pregnancy the best confirmatory test available is amniocentesis 'Triple test only gives a risk ratio. For confirmation of diagnosis, amniocentesis has to be done' - Dutta
Triple test
Amniocentesis
Cordocentesis
Chorionic villous biopsy