Non-invasive prenatal testing: impact on invasive prenatal diagnosis at a mainland Chinese tertiary medical center.

ABSTRACT

OBJECTIVE: We describe the changes over a 4-year period in the number of diagnostic testing after the introduction of non-invasive prenatal testing (NIPT). METHODS: The rate of NIPT as an indication in women who received amniocentesis, and the number of amniocentesis required for detection of one case with major aneuploidy were compared between a 1-year baseline period before the introduction of NIPT, and the 3 years following NIPT introduction. RESULTS: A total of 7536 amniocentesis procedures were performed over the 4-year study period. During the baseline period of the year 2011, the number of invasive testing required for detection of one common trisomy was 57. During the first 2 years that NIPT was offered, NIPT averaged 1.7 percent of the total indications for amniocentesis, and the required number of invasive testing decreased to 30. With the increase of the percentage of NIPT during the 3rd year, the required number of invasive testing further decreased to 26. CONCLUSION: After the clinical introduction of NIPT, invasive prenatal diagnostic testing had not decreased at a Chinese prenatal diagnostic unit, but a remarkably improved detection rate of major aneuploidies in diagnostic procedures was observed.