CHORIONIC VILLUS SAMPLING AND AMNIOCENTESIS 🎗
"Prenatal diagnosis has transformed the practice of medical genetics.” - Dr. Aubrey Milunsky 🧬 Chorionic villus sampling (CVS) and amniocentesis remain two epitomic invasive procedures in prenatal genetic diagnosis. Unlike screening approaches such as ultrasound and cell-free DNA testing, they provide diagnostic fetal-derived material for chromosomal and molecular analysis. 🔹 Chorionic villus sampling (CVS) is generally performed at 10–13 weeks of gestation. Chorionic villi are obtained from the placenta through a transabdominal or transcervical approach under ultrasound guidance. The sample can support karyotyping, chromosomal microarray, and targeted molecular testing, enabling relatively early diagnosis of conditions such as trisomy 21, 18 and 13, as well as selected single-gene disorders. 🔹 Amniocentesis is typically performed from 15 weeks onward. A small volume of amniotic fluid is collected transabdominally under ultrasound ...