TY  - RPRT
TI  - First-trimester screening: lessons from clinical trials and implementation.
AU  - Brian J Koos
PY  - 2006
DO  - 10.1097/01.gco.0000192966.29449.01
UR  - https://pubmed.ncbi.nlm.nih.gov/16601476/
ID  - 16601476
ER  -