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What is Prenatal diagnosis of Down Syndrome is by - and explain in detail?
Ans. is 'D' i.e., All of above o Screening for Down syndrome in pregnancy can be done by number of option like - Karyotyping by - Chorionic villus sampling at 10-12 weeks. Amniocentesis at 16-18 wreeks. Cordocentasis after 18 weeks. Maternal serum marker - PAPP-A and free ji HCG in first trimester. a-feto protein, HCG and estradiol (Triple test) in second trimester. Fetal USG - done in 2nd trimester to look for - Increased nuchal fold thickness. Short femur and humerus. Duodenal atresia.