Abstract:

Objective To investigate the data of 45 prenatal screen laboratories for 6 months in China,to analyze the status of prenatal screen and provide a reference for quality control. Methods All the laboratories which participated in quality assurance program in 2014 were asked to submit their data,including risk assessment software,positive cut-off value,monthly sample throughput,monthly multiple of median （mMoM） of free beta-human chorionic gonadotropin （free β-HCG） and pregnancy-associated plasma protein A （PAPPA） and trisomy 21. The data were analyzed. Results （1）A total of 33 laboratories used lifecycle system,2 laboratories used 2T-risk system,and 6 laboratories used Aiboluo system.（2）A total of 86.67%（39/45） laboratories used 1/270 as positive cut-off value for trisomy 21. There were 69.76% （30/43） laboratories with monthly sample throughput < 500 . There were 48.78%（20/41）laboratories,which their monthly positive rates for trisomy 21 had standard deviation of 1.00-7.79.（3）All the medians of free β-HCG and PAPPA existed outlier data.（4）The percentages of all mMoM for 6 months were 15.38%（6/39） in 0.90-1.10 for free β-HCG and 7.69%（3/39）in 0.95-1.05 for PAPPA. Conclusions It is not optimistic for the quality control of prenatal screen in the 1st trimester. It is difficult to use single criterion to evaluate a laboratory. It would be effective and applicable to use multiple quality control criteria for laboratories to improve quality control.

Key words: Prenatal screen in the 1st trimester, Down's syndrome, Quality control