Chorionic villus sampling in continuing pregnancies. I. Low fetal loss rates in initial 109 cases.

Among the first 150 women who agreed to have chorionic villus sampling after receiving counseling and giving informed consent, 41 proved ineligible. In six (5.5%) of the remaining 109 cases in which chorionic villus sampling was performed, we were unsuccessful in obtaining an adequate amount of villi to permit diagnostic testing. In the single loss, fetal viability was confirmed 2 weeks after sampling; however, fetal death became evident 3 weeks later. In four (3.7%) cases the pregnancies were terminated because of abnormal results, and in one (0.9%) case the pregnancy was electively terminated after normal results. Among the 41 completed pregnancies no anomalies were evident in the infants. There were two premature deliveries; one of these two infants died shortly after birth following premature rupture of the membranes at 29 weeks' gestation. All undelivered cases were progressing normally at the time of submission.