Consequences of being Rhesus D immunized during pregnancy and how to optimize new prevention strategies (original) (raw)

Risk factors for RhD immunisation despite antenatal and postnatal anti-D prophylaxis

BJOG: An International Journal of Obstetrics & Gynaecology, 2009

Objective To identify risk factors for Rhesus D (RhD) immunisation in pregnancy, despite adequate antenatal and postnatal anti-D prophylaxis in the previous pregnancy. To generate evidence for improved primary prevention by extra administration of anti-D Ig in the presence of a risk factor.

Anti-D Prophylaxis Reviewed in the Erea of Foetal RHD Genotyping

Journal of Blood Disorders & Transfusion, 2015

A few years ago, the prevention of anti-D immunization was currently based on systematic postnatal prophylaxis associated with targeted antenatal injection in high-risk situations of foeto-maternal haemorrhage. The failures of prevention are mainly due to the non-respect of established guidelines for RhIG prophylaxis, and to spontaneous undetected foetal-maternal haemorrhages without any obvious cause during the third trimester of pregnancy. In order to reduce the rate of residual post-pregnancy anti-D immunization, several countries decided to associate the classical prophylaxis to a routine antenatal anti-D prophylaxis (RAADP) during the 28th or 29th week of gestation. Since about ten years, the foetal RHD genotyping in maternal plasma enables us to limit the antenatal prophylaxis only to those D-women carrying a D+ foetus. This paper deals with: the advantages of an antenatal prevention in the light of non invasive foetal RHD genotyping, the rules rendering prevention protocols efficient whatever the algorithm applied, and the recommended immuno-haematology follow-up of women who have received RhIG.

Report of the first nationally implemented clinical routine screening for fetal RHD in Dāˆ’ pregnant women to ascertain the requirement for antenatal RhD prophylaxis

Transfusion, 2011

BACKGROUND: A combination of antenatal and postnatal RhD prophylaxis is more effective in reducing D immunization in pregnancy than postnatal RhD prophylaxis alone. Based on the result from antenatal screening for the fetal RHD gene, antenatal RhD prophylaxis in Denmark is given only to those D-women who carry a D+ fetus. We present an evaluation of the first national clinical application of antenatal RHD screening. STUDY DESIGN AND METHODS: In each of the five Danish health care regions, blood samples were drawn from D-women in Gestational Week 25. DNA was extracted from the maternal plasma and analyzed for the presence of the RHD gene by real-time polymerase chain reaction targeting two RHD exons. Prediction of the fetal RhD type was compared with serologic typing of the newborn in 2312 pregnancies, which represented the first 6 months of routine analysis. RESULTS: For the detection of fetal RHD, the sensitivity was 99.9%. The accuracy was 96.5%. The recommendation for unnecessary antenatal RhD prophylaxis for women carrying a D-fetus was correctly avoided in 862 cases (37.3%), while 39 women (1.7%) were recommended for antenatal RhD prophylaxis unnecessarily. Two RHD+ fetuses (0.087%) were not detected, and antenatal RhIG was not given. CONCLUSION: These data represent the first demonstration of the reliability of routine antenatal fetal RHD screening in D-, pregnant women to ascertain the requirement for antenatal RhD prophylaxis. Our findings should encourage the implementation of such screening programs worldwide, to reduce the unnecessary use of RhIG. ABBREVIATIONS: HDFN = hemolytic disease of the fetus and the newborn; RAADP = routine antenatal anti-D prophylaxis.

RH D Foeto-Maternal Alloimmunization Prophylaxis with Anti-D Immunoglobulins Reviewed in the Era of Foetalrhdgenotyping

Acta Clinica Belgica, 2009

In Belgium, prevention of anti-D immunization is currently based on systematic postnatal prophylaxis associated with targeted antenatal injection in high-risk situations of foeto-maternal haemorrhage. The failures of prevention are mainly due to the non-respect of established guidelines for RhIG prophylaxis, and to spontaneous undetected foetal-maternal haemorrhages without any obvious cause during the third trimester of pregnancy. In order to reduce the rate of residual post-pregnancy anti-D immunization, several countries decided to associate the classical prophylaxis to a routine antenatal anti-D prophylaxis (RAADP) during the 28th or 29th week of gestation. Since a few years, the foetal RHD genotyping in maternal plasma enables us to limit the antenatal prophylaxis only to those D-women carrying a D+ foetus. This paper deals with: the advantages of an antenatal prevention in the light of non-invasive foetal RHD genotyping, the rules rendering prevention protocols effi cient whatever the algorithm applied, and the recommended immuno-haematology follow-up of women who received RhIG.

Terminating Routine Cord Blood RhD Typing of the Newborns to Guide Postnatal Anti-D Immunoglobulin Prophylaxis Based on the Results of Fetal RHD Genotyping

Fetal Diagnosis and Therapy

Introduction: Targeted routine antenatal prophylaxis with anti-D immunoglobulin (Ig) only to RhD-negative pregnant women who carry RhD-positive fetuses (determined by fetal RHD genotyping) has reduced D-alloimmunization significantly when administered in addition to postnatal prophylaxis. Achieving high analysis sensitivity and few false-negative fetal RHD results will make RhD typing of the newborn redundant. Postnatal prophylaxis can then be given based on the result of fetal RHD genotyping. Terminating routine RhD typing of the newborns in cord blood will streamline maternity care. Accordingly, we compared the results of fetal RHD genotyping with RhD typing of the newborns. Methods: Fetal RHD genotyping was performed, and antenatal anti-D Ig was administered at gestational week 24 and 28, respectively. Data for 2017ā€“2020 are reported. Results: Ten laboratories reported 18,536 fetal RHD genotypings, and 16,378 RhD typing results of newborns. We found 46 false-positive (0.28%) and ...