Clinical utility of noninvasive fetal trisomy (NIFTY) test--early experience.

OBJECTIVE: To report the initial experience of noninvasive prenatal diagnosis of fetal Down syndrome (The NIFTY test) in a clinical setting.

METHODS: The NIFTY test was offered as a screening test for fetal Down syndrome to pregnant women with a singleton pregnancy at 12 weeks of gestation or beyond. A satisfaction questionnaire was sent to the first 400 patients.

RESULTS: During a 6-month period, 567 NIFTY tests were performed. Over 90% of those studied were ethnic Chinese, and the mean age of the women studied was 36 years. The test was performed at 12-13 weeks of gestation in 49.21%. The median reporting time was 9 days. The test was positive for trisomy 21 in eight cases, and for trisomy 18 in 1 case; all were confirmed by fetal karyotyping. There was no false-positive result. Of the questionnaires, 182 completed responses were received. Over 95% had complete or almost complete resolution of anxiety. Except for one, all were satisfied with the NIFTY test, and all indicated that they would recommend the test to their friends.

CONCLUSION: The NIFTY test was a highly specific test. Unnecessary invasive tests and associated fetal losses could be avoided in almost all women who have a normal fetus.