The Ariosa HarmonyTM Prenatal Test does not provide information on other rare chromosomal abnormalities. If the ultrasound scan shows a high nuchal translucency or other major physical defects such as brain abnormalities, heart abnormalities, the risk for some rare chromosomal defects may be high. In such cases, you may choose to have a CVS or an amniocentesis.The non-invasive prenatal test does not provide, information on other physical defects such spina bifida, or information on fetal growth. It is therefore advisable that you have all the usual ultrasound scans during your pregnancy.