Objective:

To determine the prevalence of ultrasound findings in the first and second trimesters as markers of chromosomopathies in the “Dr. Freddy Guevara Zuloaga” Perinatology Unit of the University Hospital of Caracas, Venezuela, between January 2014 and December 2024.

Methods:

Retrospective, descriptive and cross-sectional study. The statistical records of the Unit were reviewed, with a population of 98 260 patients evaluated, with 1712 cases with positive ultrasound findings in the first and second trimester.

Results:

The general prevalence of ultrasound markers was 1.74 % in the 11-year period. Among the ultrasound markers for chromosomopathies, the intracardiac echogenic focus predominated with 339 cases, representing 19.80% of all ultrasound markers, followed by absent/hypoplastic nasal bone in 276 cases and ventriculomegaly in 205 cases. It was possible to identify 26 ultrasound markers for different chromosomopathies in the first and second trimesters. Of the 1712 positive cases for ultrasound markers of chromosomopathies, 418 amniocenteses were performed for the study of fetal karyotype, finding 349 normal cases and 69 abnormal, with a prevalence of 4.0%; The highest number of cases corresponded to trisomy 21 with 34 cases for a prevalence of 49.28%, followed by trisomy 18 with 20 cases (28.99%) and trisomy 13 with 8 cases (11.59%).

Conclusion:

During the period 2014-2024, the prevalence of at least one soft ultrasound marker suggestive of chromosomal risk was 1.74% 69 abnormal karyotypes were confirmed (16.5% of procedures; 4.0% of the 1712 markers).