Kratzer P G, Golbus M S, Monroe S E, Finkelstein D E, Taylor R N
Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco 94143-0132.
Prenat Diagn. 1991 Oct;11(10):751-63. doi: 10.1002/pd.1970111003.
Immunochemical serum assays for human chorionic gonadotropin (hCG), the free ahCG subunit, and progesterone (P) were considered separately and in combination for their ability to screen for chromosomally abnormal pregnancies in the first trimester. Maternal serum was collected from 141 women undergoing chorionic villus sampling at 9-12 menstrual weeks. Trisomy 21 pregnancies had significantly higher hCG levels, while trisomy 18 and 13 pregnancies had markedly lower hCG and progesterone levels than those of chromosomally normal pregnancies. However, the discrimination of normal from aneuploid pregnancies was poor with either hCG alone, progesterone alone, or free ahCG alone. Much improved discrimination was obtained by combining hCG, free ahCG, and P into an aneuploidy index [(P/hCG)(free ahCG/hCG)]. This index distinguished 9 out of 17 (53 per cent) of the trisomy 21 pregnancies, while only misidentifying 5 out of 112 (4.5 per cent) of the normal pregnancies. The aneuploidy index thus appears promising as a first-trimester biochemical screen for aneuploid pregnancies.
分别并综合考虑了人绒毛膜促性腺激素（hCG）、游离α-hCG亚基和孕酮（P）的免疫化学血清检测方法，以评估其在孕早期筛查染色体异常妊娠的能力。收集了141名在月经周期第9至12周接受绒毛取样的孕妇的母血。21三体妊娠的hCG水平显著更高，而18三体和13三体妊娠的hCG和孕酮水平明显低于染色体正常的妊娠。然而，单独使用hCG、单独使用孕酮或单独使用游离α-hCG对正常妊娠和非整倍体妊娠的鉴别效果不佳。通过将hCG、游离α-hCG和P组合成一个非整倍体指数[（P/hCG）（游离α-hCG/hCG）]，鉴别效果有了很大改善。该指数在17例21三体妊娠中鉴别出9例（53%），而在112例正常妊娠中仅误判5例（4.5%）。因此，非整倍体指数作为孕早期非整倍体妊娠的生化筛查方法似乎很有前景。
