[1] Eastern Virginia Med Sch, Norfolk, VA 23501 USA
[2] Harvard Univ, Boston, MA 02115 USA
[3] Univ Calif Los Angeles, David Geffen Sch Med, Los Angeles, CA USA
[4] DM STAT Inc, Malden, MA USA
[5] Matenal Fetal Med Fdn, Washington, DC USA
[6] Yale Univ, New Haven, CT USA
[7] Columbia Univ, New York, NY USA
[8] Phoenix Perinatal Assoc, Phoenix, AZ USA
[9] Med Univ S Carolina, Mt Pleasant, MI USA
[10] Soc Maternal Fetal Med, Gladwyne, PA USA