Department of Obstetrics and Gynecology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
Int J Gynaecol Obstet. 2012 May;117(2):140-3. doi: 10.1016/j.ijgo.2011.11.026. Epub 2012 Feb 25.
To develop Thai-specific medians of serum pregnancy-associated plasma protein A (PAPP-A) and free β-human chorionic gonadotropin (hCG) levels during the first trimester of pregnancy and to compare these values to a Caucasian-specific model for the detection of fetal Down syndrome.
Serum concentrations of PAPP-A and free β-hCG were measured during the first trimester in a group of 2339 Thai women undergoing normal singleton pregnancies.
Thai reference ranges of PAPP-A and free β-hCG were established by gestational age (70-98 days). The equation of best fit for PAPP-A was: predicted median PAPP-A level=28.767 - 0.781×(gestational age in days)+0.006×(gestational age in days)(2); r=0.986. The equation of best fit for free β-hCG was: predicted median free β-hCG level=465.332×10((-0.024×gestational age in days)); r=0.881. Weight-corrected models were also derived for each biomarker. The Thai-specific reference ranges gave higher positive screening rates than the Caucasian-specific model, even after weight correction (5.1% versus 4.0%). The Thai-specific models were validated in an independent group of 302 pregnant women.
Ethnic group-specific medians for PAPP-A and free β-hCG should be incorporated during first-trimester screening for fetal Down syndrome.
建立泰国人群妊娠相关血浆蛋白 A（PAPP-A）和游离β-人绒毛膜促性腺激素（β-hCG）在妊娠早期的血清中位数，并将这些值与用于检测唐氏综合征胎儿的白人特异性模型进行比较。
对 2339 例接受正常单胎妊娠的泰国女性在妊娠早期进行血清 PAPP-A 和游离β-hCG 浓度检测。
根据孕龄（70-98 天）建立了泰国人群 PAPP-A 和游离β-hCG 的参考范围。PAPP-A 的最佳拟合方程为：预测中位数 PAPP-A 水平=28.767-0.781×（孕龄（天））+0.006×（孕龄（天））（2）；r=0.986。游离β-hCG 的最佳拟合方程为：预测中位数游离β-hCG 水平=465.332×10（（-0.024×孕龄（天）））；r=0.881。对每个生物标志物也推导了体重校正模型。即使经过体重校正，泰国特异性参考范围的阳性筛查率也高于白人特异性模型（5.1%比 4.0%）。在 302 例孕妇的独立组中验证了泰国特异性模型。
在唐氏综合征胎儿的妊娠早期筛查中，应纳入针对 PAPP-A 和游离β-hCG 的种族特异性中位数。
