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Phenotypic variability in fetuses with down syndrome: a case-control pathological evaluation.
C Ramalho1, O Brandão, A Matias
1Center of Prenatal Diagnosis, Department of Gynecology and Obstetrics, Centro Hospitalar S. João, Medical Faculty of Porto, Porto, Portugal. carlaramalho@med.up.pt
Fetal Diagnosis and Therapy
|September 29, 2011
Summary
Detailed postmortem examinations reveal distinct morphological and morphometric differences in fetuses with Down syndrome compared to normal fetuses. These findings enhance prenatal knowledge of Down syndrome characteristics.
Area of Science:
- Medical research
- Genetics
- Fetal development
Background:
- Down syndrome (DS) is a genetic disorder with recognizable fetal characteristics.
- Accurate prenatal diagnosis relies on understanding these characteristics.
Purpose of the Study:
- To evaluate and compare morphological and morphometric features of fetuses with Down syndrome and control fetuses.
- To enhance prenatal diagnostic knowledge of Down syndrome.
Main Methods:
- A case-control study comparing 50 fetuses with Down syndrome to 47 chromosomally normal fetuses.
- Detailed postmortem examination including biometric and morphological parameter assessment.
Main Results:
- Fetuses with Down syndrome showed significant differences in craniofacial and extremity features compared to controls.
- Specific biometric differences noted in occipitofrontal diameter and nasal bone length.
- High prevalence of internal anomalies (62%) and cardiac anomalies (38.8%) in Down syndrome fetuses.
Conclusions:
- Morphological and morphometric analysis contributes to a better understanding of fetal Down syndrome.
- This knowledge is crucial for optimizing prenatal diagnosis of Down syndrome.
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