Screening for trisomy 13 by fetal nuchal translucency and maternal serum free β-hCG and PAPP-A at 10–14 weeks of gestation

✍ Scribed by Kevin Spencer; Charas Ong; Hara Skentou; Adolfo W. Liao; Kypros H. Nicolaides

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 78 KB
• Volume: 20
• Category: Article
• ISSN: 0197-3851
• DOI: 10.1002/(sici)1097-0223(200005)20:5<411::aid-pd822>3.0.co;2-2

✦ Synopsis

In 42 cases of trisomy 13 at 10±14 weeks of gestation, compared with 947 controls, the median multiple of the median (MoM) of maternal serum free b-human chorionic gonadotrophin (b-hCG) and pregnancy associated plasma protein A (PAPP-A) was signi®cantly decreased (0.506 MoM and 0.248 MoM respectively), whilst fetal nuchal translucency was increased (2.872 MoM). In 38% and 71% of cases of trisomy 13 maternal serum free b-hCG and PAPP-A was below the 5th centile of the appropriate normal range for gestation and in 62% of cases the nuchal translucency was above the 95th centile. When combined together in a multivariate algorithm with maternal age, 90% of cases of trisomy 13 could be detected at a 0.5% false positive rate or 84% at a 0.1% false positive rate. We conclude that speci®c trisomy 13 risks should be part of developing risk algorithms combining maternal serum biochemistry and nuchal translucency for use in ®rst trimester screening alongside those for trisomy 21 and trisomy 18.