Hallazgos ecográficos en fetos con alteraciones cromosómicas

objective: to describe the abnormalities detected by detailed second trimester ultrasonography among the fetuses with abnormal karyotype after amniocentesis. methods: ultrasound studies belonging to fetuses with diagnosed chromosomal anomalies in 2006 were reviewed. setting: centro nacional de genética humana y experimental. universidad central de venezuela. caracas results: a total of 1,786 patients underwent amniocentesis with a result of 32 (1.79 %) fetuses detected with an abnormal karyotype, trisomy 21 (47 %). out of all cases with chromosomal anormalies 15 fetuses (46.9.%) had one or more sonographic markers. ultrasound markers were: increased nucal fold 40 % , cystic hygroma (19.5 %) , pyelectasis 12.5 %, and echogenic bowel, absent nasal bone, echogenic intracardiac foci and club foot (7 %) each one. a 53 % of fetuses with trisomy 21 had some adnormal sonographic marker, as well as 67 % of trisomy 18 and 100 % of fetuses with x0, trisomy 22 and triploidy. conclusions: the second trimester ultrasound plays an important role in prenatal diagnosis. the appropriate detection of structural anomalies and sonographic markers increase the diagnosis of aneuploidies and can suggest the necessity to practice an invasive study.