ABSTRACT

A systemic review of procedure-related losses for CVS and amniocentesis revealed pooled loss rates for CVS at 14 days, 30 days, and prior to 24 weeks of 0.7%, 1.3%, and 1.3%, respectively. The pooled loss rates for amniocentesis for the same time period were 0.6%, 0.8%, and 0.9% (23). Since CVS and amniocentesis are performed at different time periods, it is difficult to compare these procedures due to the higher background loss rate for the time period when CVS is performed. The benefit of earliest diagnosis with CVS compared to amniocentesis should not be underestimated. With the advent of FTS, prenatal diagnosis has moved more to the first trimester. While the total miscarriage rate is higher following first-trimester CVS because of the higher background rate in early pregnancy, for experienced centers, the rates of procedure-induced losses secondary to CVS are similar to those of second-trimester amniocentesis.