Aneuploidy among prenatally detected neural tube defects

Am J Med Genet. 1996 Jan 11;61(2):171-3. doi: 10.1002/(SICI)1096-8628(19960111)61:2<171::AID-AJMG14>3.0.CO;2-R.

Abstract

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 (19-40); 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 10/145 (7%), of which most (7/10) had trisomy 18. These data support fetal karyotyping for accurate diagnosis, prognosis, and recurrence-risk counseling.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Anencephaly / diagnosis
  • Aneuploidy*
  • Chromosomes, Human, Pair 18 / ultrastructure
  • Female
  • Humans
  • Karyotyping
  • Neural Tube Defects / diagnosis*
  • Prenatal Diagnosis*
  • Spina Bifida Cystica / diagnosis
  • Trisomy