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. Cytogenetic diagnoses resulted from 97.8 percent of the chorionic villus sampling procedures and 99.4 percent of the amniocenteses (P less than 0.05); aneuploidy was found in 1.8 and 1.4 percent, respectively, of the cases in which diagnoses were made. Of the women who underwent chorionic villus sampling, 17 (0.8 percent) subsequently had an amniocentesis because the diagnosis was ambiguous. Two of the diagnoses of aneuploidy (one tetraploidy, one trisomy 22) were later proved to be incorrect. On the basis of pediatric examination of the infants subsequently born to the women in the sample, there were no errors in the determination of sex or the identification of the major trisomies (21, 18, and 13). The rate of combined losses due to spontaneous and missed abortions, termination of abnormal pregnancies, stillbirths, and neonatal deaths was 7.2 percent in the group that underwent chorionic villus sampling and 5.7 percent in the group that had amniocentesis. After adjustment for slight differences in gestational and maternal age, the total loss rate for the women in the chorionic villus sampling group exceeded that for the amniocentesis group by only 0.8 percentage points (80 percent confidence interval, -0.6 to 2.2). The rate of loss of chromosomally normal fetuses after chorionic villus sampling was 10.8 percent among women in whom three or four attempts were made to place the transcervical catheter, as compared with 2.9 percent in those in whom only one attempt was necessary (P less than 0.01). There were no serious maternal infections among the women in this study or among an additional 1990 women who underwent chorionic villus sampling (upper 95 percent confidence limit, 0.08 percent). We conclude that chorionic villus sampling is a safe and effective technique for the early prenatal diagnosis of cytogenetic abnormalities, but that it probably entails a slightly higher risk of procedure failure and of fetal loss than does amniocentesis.

A single center’s experience with noninvasive prenatal testing

“…However, with increasing utilization of first-trimester screening and NIPT, many patients are now learning that their pregnancies are at high risk for a chromosome abnormality at a gestational age when CVS is available. Because procedure-related loss rates are comparable between CVS and second-trimester amniocentesis, 7,[14][15][16][17] many women who want definitive prenatal diagnosis may opt to have CVS in order to avoid the medical and psychological complications resulting from later prenatal diagnosis by amniocentesis.…”

Reliable detection of Trisomy 21 using MALDI-TOF mass spectrometry

“…The euploid samples had an average of 5.00 informative SNPs (range 1-11), and 23 of these (8.3%) had only 1 or 2 informative SNPs. In contrast, trisomy 21 samples had an average of 7.58 informative SNPs (range [3][4][5][6][7][8][9][10][11], and none of these had Ͻ3 informative SNPs. This difference may have contributed to the increased number of probable unaffected calls within the nontrisomy 21 samples.…”

“…2 Diagnostic methods rely on invasive techniques such as chorionic villus sampling (CVS) or amniocentesis, followed by culturing of fetal cells and karyotyping. 3,4 However, results with this method can take up to two weeks to obtain, a delay which may cause significant parental anxiety. Failure of cell culture results in the need to repeat the invasive procedure or reliance on other methods of diagnosis.…”

Reproducing Genetics

“…8 In 1986 Sherman and I moved to the Department of Obstetrics and Gynecology, University of Tennessee, Memphis, where I became chair and Sherman the director of Reproductive Genetics. The safety and efficacy of chorionic villus sampling were assessed in National Institute of Child Health and Human Development collaborative trials, 9 with Lee Shulman now joining us. Newly minted molecular technologies were evolving.…”