title: Reference values of fetal erythrocytes in maternal blood during pregnancy established using flow cytometry.
abstract: The aim of our study was to assess the fetal RBC count in maternal blood during uncomplicated pregnancies from 26 weeks onward. We used a flow cytometric method specifically designed for use in a routine hematology analyzer. Pregnant women were recruited through midwives. The participating laboratories used the FMH QuikQuant method (Trillium Diagnostics, Brewer, ME) in a CELL-DYN Sapphire hematology analyzer (Abbott Diagnostics, Santa Clara, CA). The method is based on a monoclonal antibody to hemoglobin F. Flow cytometric data were analyzed by 2 independent observers. The 95th percentile reference range was estimated according to Clinical and Laboratory Standards Institute guidelines. A total of 236 samples were statistically analyzed. Gestational ages ranged from 21.6 to 41 weeks (mean, 32.0 weeks), and the fetal RBC count in maternal blood ranged from 0.00% to 0.50% (median, 0.025%). The fetal RBC count in maternal blood shows no correlation with gestational age. The established reference range during normal pregnancy is less than 0.125%.
authors.affiliation: Abbott Diagnostics Division, Max-Planck-Ring 2, Wiesbaden-Delkenheim, Germany.
authors.forename: Harry
authors.initials: H
authors.lastname: de Wit
authors.forename: Karin C A M
authors.initials: KC
authors.lastname: Nabbe
authors.forename: Jurgen A
authors.initials: JA
authors.lastname: Kooren
authors.forename: Henk J
authors.initials: HJ
authors.lastname: Adriaansen
authors.forename: Elianne A
authors.initials: EA
authors.lastname: Roelandse-Koop
authors.forename: Joost H N
authors.initials: JH
authors.lastname: Schuitemaker
authors.forename: Johannes J M L
authors.initials: JJ
authors.lastname: Hoffmann
mesh_terms: D002469:Cell Separation; D004906:Erythrocyte Count / Q000379:methods*; D004912:Erythrocytes / Q000166:cytology*; D005260:Female; D005331:Fetomaternal Transfusion / Q000097:blood; D005333:Fetus; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D011247:Pregnancy / Q000097:blood*; D012016:Reference Values