5 links
BabyCenter
babycenter.com
Find out how an ultrasound is done, what it can tell you about your baby and when you should have it done.
How Stuff Works
howstuffworks.com
Illustrated narrative describing an assortment of testing decisions.
NT Laboratories
ntdlabs.com
Offers information on a variety of prenatal tests, including amniocentisis, and the ultra-screen.
Prenatal Testing
-cpc.org
Definitions of the following testing procedures: amnioscentesis, ultrasound, chorionic villi sampling, and fetal development.