The trisomy 18 syndrome, also known as Edwards syndrome, is a common chromosomal disorder due to the presence of an extra chromosome 18, either full, mosaic trisomy, or partial trisomy 18q. The live born prevalence is estimated as 1/6000 - 1/8000. The prevalence of trisomy 18 rises with the increasing maternal age. The recurrence risk for a family with a child with full trisomy 18 is about 1%. Currently most cases of trisomy 18 are prenatally diagnosed, based on screening by maternal age, maternal serum marker screening, or detection of sonographic abnormalities (growth retardation, choroid plexus cyst, overlapping of fingers, and congenital heart defects). Typical minor anomalies include characteristic craniofacial features, small fingers and fingernails, underdeveloped thumbs, and short sternum. The major malformations is common, and the most frequent are heart and kidney anomalies.