How do the trends in the prenatal diagnosis of aneuploidy change after a non-invasive prenatal test becomes available? A Japanese single center study

Purpose: To clarify the trends in the use of the prenatal diagnosis of and screening for aneuploidy after a non-invasive prenatal test (NIPT) was made available at a single Japanese hospital. Methods: The subjects included consecutive pregnant females who visited our hospital for maternal checkups and delivery between January 2012 and April 2014. After the subjects were divided into those who desired a prenatal diagnosis or screening before the availability of NIPT and those who did after the availability of NIPT, the frequencies of various prenatal diagnosis and screening procedures were compared between the two groups. Results: A total of 544 patients who visited the hospital before NIPT was available and 703 who visited the hospital after NIPT became available were analyzed. While only 16.2 % of pregnant females received a prenatal diagnosis or screening before the NIPT was available, 27.5 % of them considered undergoing a prenatal diagnosis or screening after the NIPT was available before genetic counseling, and 24.0 % ultimately received a prenatal diagnosis or screening following genetic counseling. Of these patients, 7.7 % underwent NIPT. First trimester ultrasound screening for chromosomal abnormalities was unlikely to be selected (from 12.9 to 10.5 %, p = 0.212), although the rate of amniocentesis significantly increased after genetic counseling (from 1.5 to 3.7 %, p = 0.021). Conclusion: Since NIPT became available in 2013, pregnant females have demonstrated a deep interest in obtaining a prenatal diagnosis and screening. Whereas some patients choose to forgo a screening after receiving genetic counseling, others prefer invasive diagnostic tests in contrast to screening.