The concentration of fetal red blood cells in first-trimester pregnant women undergoing uterine aspiration is below the calculated threshold for Rh sensitization.

Contraception
Sarah HorvathCourtney A Schreiber

Abstract

To calculate the minimum fetal red blood cell concentration required to cause maternal Rh sensitization; validate the use of a flow cytometry protocol below that concentration; preliminarily assess the concentrations of fetal red blood cells in pregnant women before and after uterine aspiration. Using pre-existing literature, we calculated the lowest concentration of fetal red blood cells found to cause sensitization within adult female circulation. We validated a two-color flow cytometry protocol using fluorescently labeled antibodies to Hemoglobin F (expressed by fetal red blood cells and adult F cells) and Carbonic Anhydrase (expressed in red blood cells during the third trimester and postnatally) by titrating second trimester cord blood into non-pregnant adult blood. We applied this flow cytometry protocol in a prospective cohort study of 42 pregnant women at 5-12 weeks gestational age undergoing uterine aspiration for induced or spontaneous abortion. The calculated threshold for causing Rh sensitization was 250 fetal red blood cells per 10 million total red blood cells. We showed a linear relationship between observed and expected fetal red blood cell fractions in titrated samples. Fetal red blood cell counts were more rel...Continue Reading

References

Dec 28, 1978·The New England Journal of Medicine·G J DoverK Heintzelman
Jun 26, 1991·JAMA : the Journal of the American Medical Association·G F ChávezL D Edmonds
Mar 1, 1989·American Journal of Clinical Pathology·S J NanceG Garratty
Jun 16, 1973·Lancet·M E PembreyJ B Clegg
Apr 1, 1996·Clinical Biochemistry·S Aliakbar, P R Brown
Mar 14, 2003·American Journal of Obstetrics and Gynecology·Sami Jabara, Kurt T Barnhart
Apr 24, 2004·Transfusion·George GarrattyUNKNOWN Retrovirus Epidemiology Donor Study
Sep 1, 2007·Klinische Pädiatrie·E Kohne
Nov 6, 2009·Obstetrics and Gynecology·Reem HasanKatherine E Hartmann
Apr 18, 2013·International Journal of Laboratory Hematology·B D Hedley, M Keeney
Mar 5, 2016·The Journal of Obstetrics and Gynaecology Research·T UmazumeH Minakami
Jun 21, 2016·International Journal of Laboratory Hematology·A GielezynskaE Kraszewska
Jul 26, 2017·Obstetrics and Gynecology·UNKNOWN Committee on Practice Bulletins-Obstetrics
Sep 15, 2017·American Journal of Perinatology·Jeffrey D SperlingSuneet P Chauhan
Aug 30, 2018·Obstetrics and Gynecology·UNKNOWN American College of Obstetricians and Gynecologists' Committee on Practice Bulletins—Gynecology
Nov 28, 2019·MMWR. Surveillance Summaries : Morbidity and Mortality Weekly Report. Surveillance Summaries·Tara C JatlaouiMaura K Whiteman

❮ Previous
Next ❯

Citations

Mar 17, 2020·Journal of Assisted Reproduction and Genetics·Andres ReigEmre Seli
Aug 10, 2020·Current Opinion in Obstetrics & Gynecology·Sarah F Peterson, Klaira Lerma
Nov 7, 2020·BMJ Sexual & Reproductive Health·Jonathan Lord
Jul 30, 2021·Clinical Obstetrics and Gynecology·Andrea Henkel, Kate A Shaw
Aug 23, 2021·Current Opinion in Obstetrics & Gynecology·Taylor Stanton, Deborah Bateson

❮ Previous
Next ❯

Related Concepts

Related Feeds

Allergy and Asthma

Allergy and asthma are inflammatory disorders that are triggered by the activation of an allergen-specific regulatory t cell. These t cells become activated when allergens are recognized by allergen-presenting cells. Here is the latest research on allergy and asthma.