National Support Organizations

Often times families in the midst of early grief do not realize that there are national support organizations that deal with very specific genetic or fetal anamoly issues. If you know of organizations that were helpful to you or someone you know, please share some here. For example:

http://www.trisomy18.org/site/PageServer
http://www.marchofdimes.com/mission/prematurity.html
http://www.cjsids.org/
http://www.ndss.org/
http://www.americanpregnancy.org/pregnancycomplications/miscarriage.html