References
Down Syndrome Detection Rate:
Krantz et al, First Trimester Down Syndrome screening Using Dried Blood Biochemistry and Nuchal translucency. Obstet. Gynecol. 2000;96:207-13
Pirni et. al Am J Obstet Gynecol. (2006) 194, 127-30
Free Beta hCG vs. Total Beta hCG
| Author | # of Patients | False Positive Rate % | Detection Rate % |
| Orlandi (1997) | 744 | 5 | 87 |
| Biagiotti (1998) | 232 | 5 | 76 |
| De Biasio (1999) | 1467 | 3.3 | 85 |
| De Graaf (1999) | 300 | 5 | 85 |
| Spencer (1999) | 1156 | 5 | 89 |
| Krantz (2000) | 5718 | 5 | 91 |
| Niemimaa (2001) | 1602 | 5.4 | 80 |
| Wapner (BUN) (2002) | 8514 | 5 | 79 |
| Schucter (2002) | 4939 | 5 | 86 |
| Von Kaisenberg (2002) | 3864 | 6.6 | 84 |
| Bindra (2002) | 15030 | 5 | 90 |
| Spencer (2003) | 10458 | 5 | 92 |
| Sheffield (2003) | 18140 | 5 | 94 |
| Borrell (2004) | 2780 | 3.3 | 88 |
| Stenhouse (2004) | 5084 | 5.9 | 93 |
| Nicolaides (2005) | 75821 | 5.2 | 93 |
| Malone (2005) | 33546 | 5.6 | 86 |
| Pirni (2006) | 4883 | 5 | 91 |
| Total | 194278 | 5.2 | 89 |
Trisomy 18/13 Detection/False Positive Rate:
Spencer and Nicolaides. A first trimester trisomy 18/trisomy 13 risk algorithm combining fetal nuchal translucency thickness, maternal serum free Beta and PAPP-A. Prenat. Diagn. 2002;22:877-879
Nasal Bone Detection/False Positive Rate:
Cicero et al. Integrated Ultrasound and Biochemical screening for trisomy 21 using fetal nuchal translucency, absent fetal nasal bone, free Beta hCG and PAPP-A at 11 to 14 weeks.Prenat Diagn 2003;23:306-310.
(Evans et al. Meta-Anaysis of first trimester Down syndrome screening studies: free Beta human chorionic gonadotropin significantly outperforms intact human chorionic gonadotropin in a multimarker protocol. Am J Obstet Gynecol. 2007;196:198-205)
Nasal Bone Absence in 70% of Down Syndrome Cases:
- Cicero et al. Lancet. 2001;358:1665-7.
- Otano et al. Prenat Diagn. 2002;22:930-2.
- Zoppi et al. Prenat Diagn. 2003;23:496-500.
- Orlandi et al. Ultrasound Obstet Gynecol. 2003;22:36-9.
- Viora et al. Prenat Diagn. 2003;23:784-7.
- Senat et al. Ultrasound Obstet Gynecol. 2003;22:138-41.
- Wong et al. Gynecol Obstet Invest. 2003;56:99-101.
- Cicero et al. Ultrasound Obstet Gynecol. 2003;22:31-5.
- Cicero et al. Prenat Diagn. 2003;23:306-10.
- Cicero et al. Ultrasound Obstet Gynecol. 2004;23:218-23.
- Orlandi et al. Am J Obstet Gynecol. 2005;192:1107-11.
- Nicolaides et al Ultrasound Obstet Gynecol 2005;25:221-26.
ACOG Practice Bulletin:
ACOG Practice Bulletin No 77, Jan. 2007, Level A Recommendations. ACMG Practice Guideline, Nov/Dec. 2004, Vol. 6, No. 6.
Published Studies
| Intact HCG Studies | Median MoM | Cases |
| Cuckle '88 | 1.1 | 22 |
| Bogart '89 | 1.1 | 6 |
| Brock '90 | 1.43 | 19 |
| Johnson '91 | 0.9 | 11 |
| Kratzer '91 | 1.23 | 17 |
| Van Lith '92 | 1.14 | 24 |
| Aitken '93 | 0.97 | 14 |
| Crandall '93 | 1.73 | 11 |
| Iles '93 | 1.35 | 25 |
| MacIntosh '94 | 1.4 | 20 |
| Brizot '95 | 1.5 | 41 |
| Forest '95 | 1.83 | 12 |
| Cassals '96 | 1.38 | 19 |
| Aitken '96 | 1.05 | 14 |
| Jauniaux '96 | 0.96 | 17 |
| Free Beta hCG Studies | ||
| Ozturk | 1.62 | 9 |
| Spencer | 1.85 | 13 |
| Isles | 1.52 | 25 |
| Macri | 2.34 | 25 |
| Pescia | 2.03 | 5 |
| Brambati | 1.13 | 13 |
| Kellner | 2.2 | 5 |
| Forest | 1.92 | 18 |
| MacIntosh | 2.1 | 21 |
| Biagiotti | 2 | 41 |
| Brizot | 2 | 41 |