Utilization of second trimester maternal serum screening for down syndrome by advanced maternal age women Peter Benn, James Egan American Journal of Obstetrics & Gynecology Volume 191, Issue 6, (December 2004) DOI: 10.1016/j.ajog.2004.10.035 Copyright © 2004 Elsevier Inc. Terms and Conditions
American Journal of Obstetrics & Gynecology 2004 191, DOI: (10. 1016/j American Journal of Obstetrics & Gynecology 2004 191, DOI: (10.1016/j.ajog.2004.10.035) Copyright © 2004 Elsevier Inc. Terms and Conditions