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Updated: May 23, 2026
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Chromosome Screening of Human Preimplantation Embryos by Using Spent Culture Medium: Sample Collection and Chromosomal Ploidy Analysis
Published on: September 7, 2021
Increased nuchal traslucency in normal karyotype fetuses
Roberta De Domenico1, Marianna Faraci, Entela Hyseni
1Policlinico Universitario "G. Martino", Department of Obstetrics and Gynecology, University of Messina, Italy.
Journal of Prenatal Medicine
|March 23, 2012
Summary
Increased nuchal translucency (NT) in chromosomally normal fetuses does not significantly increase risks for adverse pregnancy outcomes or developmental delays. Parents can be reassured about the low residual chance of anomalies.
Area of Science:
- Maternal-fetal medicine
- Prenatal diagnostics
- Genetics
Background:
- Nuchal translucency (NT) measurement is a key first-trimester screening tool for chromosomal abnormalities.
- Increased NT, even with normal karyotyping, is linked to adverse pregnancy outcomes and fetal malformations.
- Many structural anomalies associated with increased NT are not detectable by standard prenatal screening.
Purpose of the Study:
- To evaluate the pregnancy outcomes and neurodevelopmental status of chromosomally normal fetuses with increased NT.
- To provide reassurance to parents regarding the risks associated with isolated increased NT.
Main Methods:
- Retrospective analysis of pregnancies with NT measurements between 11-14 weeks' gestation.
- Inclusion of cases with normal karyotyping and detailed ultrasound/echocardiography.
- Comparison of outcomes and neurodevelopmental data with the general population.
Main Results:
- Increased NT thickness, particularly ≥3.5 mm, correlates with higher risks.
- Chromosomally normal fetuses with enlarged NT, even without detectable anomalies, show no statistically significant increase in adverse outcomes or developmental delay.
- Uneventful outcomes are common in this group.
Conclusions:
- Isolated increased nuchal translucency in chromosomally normal fetuses generally carries a low risk for significant adverse outcomes.
- Parents of these fetuses can be confidently reassured about the low residual risk of structural anomalies and abnormal neurodevelopment.
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