Increased nuchal translucency and pregnancy outcome

Area of Science:

• Maternal-fetal medicine
• Prenatal diagnosis
• Genetics

Background:

• Nuchal translucency (NT) screening is a key first-trimester pregnancy assessment.
• An enlarged NT (≥ 95th centile) is associated with increased risks of adverse outcomes.
• Understanding these risks is crucial for genetic counseling and management.

Purpose of the Study:

• To investigate the pregnancy outcomes for fetuses with nuchal translucency (NT) ≥ 95th centile.
• To assess the incidence of chromosomal abnormalities and fetal malformations in this group.
• To determine the overall risk of adverse pregnancy outcomes.

Main Methods:

• A cross-sectional study of 186 cases with NT ≥ 95th centile was conducted.
• Follow-up included anomaly scans and fetal echocardiography.
• Pregnancy outcomes were meticulously recorded through delivery records, pediatric notes, and interviews.

Main Results:

• 19.8% of fetuses had abnormal karyotypes, including trisomies 21, 18, 13, and Turner syndrome.
• 77.8% showed no abnormalities on follow-up.
• Adverse outcomes included malformations (4.6% antenatal, 4% postnatal), termination (11.4%), fetal loss (4.6%), and hydrops fetalis (1.3%).

Conclusions:

• Approximately 25% of fetuses with enlarged NT experienced adverse pregnancy outcomes.
• Despite risks, 95% of pregnancies resulted in a normal child after excluding chromosomal abnormalities and fetal loss.
• First-trimester NT screening aids in identifying high-risk pregnancies requiring further evaluation.