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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Antenatal screening test done in the maternal serum is _______
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The correct answer is  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