<prompt> Antenatal screening test done in the maternal serum is ___Percutaneous unbilical blood samplingCell-free fetal DNA testingChorionic villus samplingAmniocentesis  <response>: Antenatal screening test done in the maternal serum is cell-free fetal DNA testing, which is a non-invasive prenatal screening. This test is done using the freely circulating fetal cells in the maternal serum. It is useful for karyotyping and for detecting single gene disorders. Invasive procedures for prenatal diagnosis Chorionic villous sampling CVS Amniocentesis Cordocentesis or percutaneous umbilical blood sampling PUBS Ref: Nelson textbook of pediatrics 21st edition Pgno: 969 