The Safety and Efficacy of Chorionic Villus Sampling for Early Prenatal Diagnosis of Cytogenetic Abnormalities

Abstract

Chorionic villus sampling is a method of prenatal diagnosis in the first trimester of pregnancy in which tissue for genetic study is aspirated from the developing placenta by means of a catheter inserted transcervically under the guidance of ultrasonography. In this seven-center study, we compared the safety and efficacy of chorionic villus sampling in 2278 women with those of amniocentesis at 16 weeks' gestation in 671 women. Both groups were made up primarily of well-educated private patients; they were recruited in the first trimester of pregnancy and had viable pregnancies verified by ultrasound examination.