Second trimester ultrasound screening for chromosomal abnormalities.

摘要: The use of prenatal ultrasound has proven efficacious for the diagnosis chromosomal abnormalities. first sonographic sign Down syndrome, thickened nuchal fold, was described in 1985. Since that time, multiple sonographically-identified markers have been as associated with syndrome. genetic sonogram, involving a detailed search signs aneuploidy, can be used to both identify fetuses at high risk aneuploidy and, when normal, decrease pregnancy no are identified. Combining sonogram maternal serum screening may best method assessing women who desire such an assessment second trimester. Trisomy 18, 13, and triploidy typically sonographically identified abnormalities detection rate. low-risk requires further investigation, however, patients increased due advanced age or abnormal benefit from adjust their baseline affected fetus.