ABSTRACT
INTRODUCTION e diagnosis of fetal cytogenetic abnormalities in the rst trimester of pregnancy by chorionic villus sampling (CVS) has been a routine part of obstetrical care for over three decades. In the last 20 years, based on its proven safety and ability to provide a diagnosis earlier in pregnancy than amniocentesis, CVS has become the primary prenatal diagnostic approach in many centers. However, due to the continued improvement in noninvasive aneuploidy screening the use of all diagnostic procedures, including CVS, has decreased by over 33% to more and 50% in the last 5 years.1,2 Despite this decrease in routine use, the procedure remains a valuable technique for the diagnostic evaluation of screen positive patients, for diagnosing disorders not amenable to noninvasive screening, and for providing an option for couples who desire to maximize the available cytogenetic information about the pregnancy.
