TY  - RPRT
TI  - First trimester screening.
AU  - Sarah C Ellestad
AU  - Steven R Wells
AU  - Jeffrey A Kuller
PY  - 2005
DO  - 10.1159/000083485
UR  - https://pubmed.ncbi.nlm.nih.gov/15687731/
ID  - 15687731
ER  -