[First trimester ultrasound: an early screening tool for fetal structural and chromosomal abnormalities].

Background: Prenatal diagnosis has been greatly expanded in recent years. Many biological and sonographic criteria participated in the development of fetal medicine.

Aim: Analyze the contribution of first trimester ultrasound in prenatal diagnosis of aneuploidy and early fetal malformations, and its impact on the strategy of prevention of disability.

Methods: A prospective longitudinal descriptive study including all women who did a first trimester ultrasound during their pregnancy. We evaluated the detection rate of malformations and chromosomal abnormalities of the morphological embryonary study and nuchal translucency. These tests were then confronted with the results of fetal samples and the outcome of pregnancy.

Results: 593 ultrasound examinations were performed. The average age of pregnant women was 32.7 years. The mini-morphological ultrasound study revealed 26 abnormalities (3 major lethal malformations, 5 cystic hygroma and 18 increased nuchal translucency). Chromosomal abnormalities were found in six cases. The first trimester ultrasound has ensured the detection of 2/3 of total aneuploidies of the study.

Conclusion: The first trimester ultrasound allows early detection of a large number of aneuploidies and fetal malformations.