[1] Beth Israel Deaconess Med Ctr, Dept Pathol, Boston, MA USA
[2] Harvard Med Sch, Boston, MA USA
[3] Harvard Med Sch, Beth Israel Deaconess Med Ctr, Div Maternal Fetal Med, Boston, MA USA
[4] Kingston Hlth Sci Ctr, Dept Pathol & Mol Med, Kingston, ON, Canada
[5] Queens Univ, Kingston, ON, Canada
[6] Univ Southern Calif, Dept Obstet & Gynecol, Los Angeles Fetal Surg, Los Angeles, CA USA
[7] Boston Childrens Hosp, Div Maternal Fetal Med, Boston, MA USA
[8] Sunnybrook Hlth Sci Ctr, Dept Lab Med & Pathobiol, Toronto, ON, Canada
[9] Virginia Commonwealth Univ, Dept Pathol, Richmond, VA USA
[10] Sunnybrook Hlth Sci Ctr, Div Maternal Fetal Med, Toronto, ON, Canada
[11] Beth Israel Deaconess Med Ctr, Blood Bank, YA-309,330 Brookline Ave, Boston, MA 02215 USA