Aneuploidy among prenatally detected neural tube defects

✍ Scribed by Hume, Roderick F.; Drugan, Arie; Reichler, Avi; Lampinen, Jenifer; Martin, Laura S.; Johnson, Mark P.; Evans, Mark I.

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 16 KB
• Volume: 61
• Category: Article
• ISSN: 0148-7299
• DOI: 10.1002/(sici)1096-8628(19960111)61:2<171::aid-ajmg14>3.0.co;2-r

✦ Synopsis

We have reported previously a 10% aneuploidy detection rate among 39 cases of fetal neural tube defects (NTD). Subsequently we amassed an additional experience of over 17,000 prenatal diagnosis cases over a 5-year period. During this period 106 cases of NTDs were identified; 44 with anencephaly, 62 with open spina bifida. The average maternal age of this population with NTDs was 29 years (15-40); 6 patients declined amniocentesis. Six of 100 cytogenetic studies were aneuploid; one anencephalic fetus had inherited a maternal marker chromosome, and 5 NTD cases had trisomy 18. The average maternal age of the aneuploid cases was 31 (1940); 3 were 35 years or older. Four of 5 trisomy 18 cases had multiple congenital anomalies (MCA). The overall aneuploidy detection rate in our cohort was 5-6%, while aneuploidy occurred in 2% of the isolated NTD cases, and 24% of the MCA cases. Combining the earlier experience, 4/39 aneuploidy (2 trisomy 18,4p+, del 13q) yields an aneuploidy detection frequency of 101145 (7%), of which most (7/10) had trisomy 18. These data support fetal karyotyping for accurate diagnosis, prognosis, and recurrence-risk counseling.