Objective The aims of this study were to determine the rate of change by type of diagnosis by transabdominal chorionic villus sampling (TA-CVS) vs. amniocentesis for aneuploidy and to describe a successful and intensive international training program for TA-CVS in ongoing pregnancies. Methods We conducted a retrospective cohort study of all deliveries from 2010 to 2018 in Sardinia. All invasive diagnostic procedures are conducted at a single regional perinatal referral center. Descriptive statistics were used to compare data across groups, and inter-correlations between variables were investigated by Pearson's correlation coefficient. We subsequently describe the international trainee experiences in TA-CVS over a 35-year period. Results A total of 101,025 deliveries occurred over 9 years. The number of deliveries (13,413-9143, P < 0.0001) and total invasive diagnostic procedures (1506-858 per year, P = 0.019) declined over this period. The percentage of deliveries undergoing invasive diagnostic procedures remained steady (mean: 12.2%). In 2010, TA-CVS made up 32.3% of all invasive diagnostic procedures, while amniocentesis made up 67.7%. By 2018, TA-CVS made up 61.3% of the invasive diagnostic procedures, and amniocentesis, only 38.7%. The rate of TA-CVS increased over 9 years, while the rate of amniocentesis declined. A total of 236 trainees from 39 different countries and 5 different continents rotated through this site. The average length of stay was 2.4 weeks. Conclusion We demonstrate an increasing prevalence of TA-CVS vs. amniocentesis in the current era of prenatal testing and underscore the importance of continuing to train specialists skilled in TA-CVS. Our global operative experience is feasible and sustainable and will have a lasting impact on physicians conducting invasive fetal procedures.
Keywords: amniocentesis; chorionic villous sampling; fetal cell-free DNA; prenatal screening; training in invasive prenatal procedures.