Benn P A, Clive J M, Collins R
University of CT Health Center, Division of Human Genetics, Department of Pediatrics, Farmington 06030-6140, USA.
Clin Chem. 1997 Feb;43(2):333-7.
Second-trimester maternal serum alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3) are routinely measured in screening fetuses at high risk for Down syndrome or open neural tube defects (ONTD). For test interpretation, individual patient values of these three analytes are related to population-derived median values. We evaluated data from >21000 pregnancies to determine the extent of race-specific differences in median concentrations. For samples at most gestational ages, median AFP, hCG, and uE3 values for white, black, Hispanic, and other patients were all significantly different. Differences remained significant even when data were corrected for patient weights. For each analyte, the extent of the variation was not the same at different gestational ages. Differences in median values across race/ethnicity groups appear to have only a small impact in Down syndrome screening but it may be appropriate to use alternative sets of AFP medians or adjustment factors to AFP medians for some Asian populations receiving ONTD screening.
孕中期母体血清甲胎蛋白（AFP）、人绒毛膜促性腺激素（hCG）和非结合雌三醇（uE3）常用于筛查唐氏综合征或开放性神经管缺陷（ONTD）的高危胎儿。在检测结果解读时，这三种分析物的个体患者值与群体衍生的中位数相关。我们评估了超过21000例妊娠的数据，以确定中位数浓度的种族特异性差异程度。对于大多数孕周的样本，白人、黑人、西班牙裔和其他患者的AFP、hCG和uE3中位数均存在显著差异。即使对患者体重进行数据校正后，差异仍然显著。对于每种分析物，不同孕周的变化程度也不相同。种族/族裔群体之间中位数的差异在唐氏综合征筛查中似乎影响较小，但对于一些接受ONTD筛查的亚洲人群，使用AFP中位数的替代集或AFP中位数的调整因子可能是合适的。
