engleski

Ultrasonic markers of fetal chromosomal abnormalities

OBJECTIVE: The aim of this brief investigation was to correlate the most common sonographically detectable markers with certain type of chromosomal disorder diagnosed by available karyotyping procedures. STUDY DESIGN: During the 3 year study period fetal karyotyping was performed in 1055 patients for a variety of clinical indication. Twenty one percent (21% ; 222/1055) of procedures were done because of sonographically detectable structural disorders related to phenotype expression of chromosomopathies. Sonographic examinations and karyotyping procedures were performed between the 10th and 36th week. The average maternal age was 27 years, unselected. RESULTS: The fetal karyotype was abnormal in 13.5% of cases (30/222). Within the group of single marker, 11.6% (7/60) of karyotypes were abnormal. Multiple markers of chromosomal abnormalities resulted in 14.2% (23/162) of abnormal karyotypes. The most frequent chromosomal disorder detected in sonographic screening is trisomy 18 (50% ; 15/30). The data on the frequency of different types of chromosomal abnormalities are given. CONCLUSIONS: The incidence of chromosomal abnormalities for ultrasonographically detectable malformations is much higher than the incidence reported in screening studies based on maternal age or biochemical screening. Trisomy 21 showed the relative lack of variety in phenotypic expression, and nuchal translucency screening has to be accepted rationally. Associated numerous major and minor malformations were the most prominent factors leading to the diagnosis of chromosomopathies, particularly trisomy 18.

chromosomal abnormalities ; ultrasonography ; screening

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