History of Amazon Reveals Original Name and Jeff Bezos' Temper. A number of little-known facts surrounding Amazon's rise as an ecommerce powerhouse are explored in a new book called The Everything Store: Jeff Bezos and the Age of Amazon by Businessweek senior writer Brad Stone, released on Tuesday.
There are four basic types of screening tests for Down syndrome. Some of these tests need to be done early in the pregnancy, while one is not done until 15 to 18 weeks of pregnancy (at around 4 months). âFirst-trimester screening is typically done at 11 to 13 weeks of pregnancy.
CVS is usually performed between 10 and 13 weeks from your last menstrual period. CVS may be chosen over amniocentesis because it may be performed earlier in the pregnancy. Chorionic villus sampling detects chromosome abnormalities (i.e. Down syndrome) and genetic disorders (i.e. cystic fibrosis.). This test is different from amniocentesis in that it does not allow for testing for neural tube defects. Chorionic villus sampling also provides access to DNA for paternity testing prior to delivery.