Ultrasound Identification of Morphological features in Trisomy 13 (Patau's Syndrome) Fetuses

Trisomy 13 (Patau's syndrome), a chromosomal abnormality, has a poor prognosis. Fetal ultrasound helps in the early detection of trisomy 13. The present study describes the typical morphological features of trisomy 13 detected on prenatal ultrasound in fetuses.

The study compared 50 fetuses with trisomy 13 to 4,166 normal fetuses. It collected maternal age and medical history, performed fetal ultrasound in the first and second trimesters, and recorded all the major structural abnormalities.

The study found-

• Trisomy 13 in 98% of fetuses on ultrasound in the first and second trimesters. 
• 18 among 23 fetuses examined in the first trimester showed increased nuchal translucency (NT ? 3 mm).
• Facial malformations (53.85%), brain anomalies (26.92%), heart defects (26.92%), abdominal wall abnormalities (23.08%), and kidney anomalies (26.92%) were the major structural abnormalities detected in fetuses with trisomy 13.
• 18% of trisomy 13 cases were not detected on ultrasound.

This study suggests increased NT and major structural abnormalities as the early signs of trisomy 13 by ultrasound. The combination of fetal ultrasound and other prenatal screening methods can detect fetal abnormalities early and precisely. 

Tran DC, et al. Typical Morphological Features on Prenatal Ultrasound of Fetuses With Trisomy 13 (Patau's Syndrome). J Clin Gynecol Obstet. 2023;12(1):8-14. doi: https://doi.org/10.14740/jcgo848