Transabdominal chorion villus sampling: a safe and reliable procedure.

A complete follow-up of the first 578 patients undergoing transabdominal chorion villus sampling (TACVS) in our combined practices was undertaken to determine the pregnancy loss rate. Factors contributing to losses and the problems incurred in achieving a clinically relevant result were also examined. It was found that increasing experience led to fewer procedural difficulties but that there persisted a higher problem rate in those women with a retroverted uterus. In 98.1% of patients an adequate volume of tissue was obtained and in 95.5% a clinically relevant result was achieved. This second figure rose to 96.3% in the latter part of the study. There was a total fetal loss rate of 2%, with only 0.5% (3 patients) having a missed abortion within 4 weeks of the procedure. It is concluded that TACVS is a reliable procedure with a high level of safety.