Wolf G C, Byrn F W, McConnell T S, Khazaeli M B
Department of Obstetrics and Gynecology, University of New Mexico School of Medicine, Albuquerque.
Prenat Diagn. 1992 Feb;12(2):93-101. doi: 10.1002/pd.1970120204.
Amniotic fluid from 135 pregnancies was assayed for human chorionic gonadotropin (hCG) and its free alpha (ahCG) and free beta (bhCG) subunits. Forty-six chromosomally abnormal pregnancies between 14 and 20 weeks' gestation were matched with 89 chromosomally normal samples. Compared with controls, trisomy 21 pregnancies exhibited significantly elevated levels of all three peptides, whereas trisomy 18 gestations gave rise only to significant elevation of ahCG. Female fetuses in both the trisomy 21 and trisomy 18 pregnancies provided significantly elevated levels of hCG and bhCG compared to their male counterparts. On converting the values to multiples of the median, it was determined that 6 of 7 trisomy 18 samples had abnormally elevated alpha/beta ratios, as did 6 of 21 Down's syndrome pregnancies. Further, 11 of 21 trisomy 21 gestations had abnormal amniotic fluid hCG levels. Using only ahCG, bhCG and their ratio, a 61 per cent sensitivity was found for these trisomies, with a 96 per cent specificity.
对135例妊娠的羊水进行了人绒毛膜促性腺激素（hCG）及其游离α亚基（αhCG）和游离β亚基（βhCG）的检测。将46例孕14至20周的染色体异常妊娠与89例染色体正常样本进行匹配。与对照组相比，21三体妊娠的所有三种肽水平均显著升高，而18三体妊娠仅导致αhCG显著升高。21三体和18三体妊娠中的女性胎儿与男性胎儿相比，hCG和βhCG水平显著升高。将这些值转换为中位数倍数后，发现7例18三体样本中有6例α/β比值异常升高，21例唐氏综合征妊娠中有6例也是如此。此外，21例21三体妊娠中有11例羊水hCG水平异常。仅使用αhCG、βhCG及其比值，这些三体综合征的检测灵敏度为61%，特异性为96%。
