Prevalence of trisomy in countries worldwide.

This study evaluated prenatal screening test performance and the prevalence of common aneuploidies at Siriraj Hospital, Thailand. We collected data from screening tests which are first-trimester test, quadruple test, and noninvasive prenatal tests (NIPT) between January 2016 and December 2020. Thirty percent (7,860/25,736) of pregnancies received prenatal screening tests for aneuploidies disorders, and 17.8% underwent prenatal diagnosis tests without screening. The highest percentage of screening tests was first-trimester test (64.5%). The high-risk results were 4% for first-trimester test, 6.6% for quadruple test, and 1.3% for NIPT. The serum screening tests for trisomy 13 and 18 had no true positives; therefore, we could not calculate sensitivity. For the first-trimester test, the sensitivity for trisomy 21 was 71.4% (95% confidence intervals (CI) 30.3–94.9); specificity for trisomy 13 and 18 was 99.9% (95% CI 99.8–99.9); and for trisomy 21 was 96.1% (95% CI 95.6–96.7). For the quadruple test, the specificity for trisomy 18 was 99.6% (95% CI 98.9–99.8), while the sensitivity and specificity for trisomy 21 were 50% (95% CI 26.7–97.3) and 93.9% (95% CI 92.2–95.3), respectively. NIPT had 100% sensitivity and specificity for trisomy 13, 18 and 21, and there were neither false negatives nor false positives. For pregnant women

本研究针对泰国诗里拉吉医院（Siriraj Hospital）的产前筛查检测性能及常见染色体非整倍体（aneuploidies）的患病率展开评估。研究收集了2016年1月至2020年12月期间的三类产前筛查检测数据，分别为早孕期筛查检测（first-trimester test）、四联筛查检测（quadruple test）以及无创产前检测（noninvasive prenatal tests, NIPT）。共有30%（7860/25736）的妊娠人群接受了针对染色体非整倍体疾病的产前筛查，另有17.8%的妊娠人群未进行产前筛查直接接受产前诊断检测。占比最高的筛查类型为早孕期筛查检测，达64.5%。
各类筛查的高风险结果占比分别为：早孕期筛查检测4%、四联筛查检测6.6%、无创产前检测1.3%。针对13-三体与18-三体的血清筛查检测未发现真阳性病例，因此无法计算其检测灵敏度。针对早孕期筛查检测：其针对21-三体的灵敏度为71.4%（95%置信区间（CI）30.3~94.9）；针对13-三体与18-三体的特异度为99.9%（95%置信区间（CI）99.8~99.9）；针对21-三体的特异度为96.1%（95%置信区间（CI）95.6~96.7）。针对四联筛查检测：其针对18-三体的特异度为99.6%（95%置信区间（CI）98.9~99.8），针对21-三体的灵敏度与特异度分别为50%（95%置信区间（CI）26.7~97.3）与93.9%（95%置信区间（CI）92.2~95.3）。无创产前检测针对13-三体、18-三体及21-三体均展现出100%的灵敏度与特异度，未出现假阴性与假阳性病例。针对妊娠女性