Estimating the cost of Rh testing and prophylaxis in early pregnancy: A time-driven activity-based costing study.

OBJECTIVE: To estimate the cost of Rhesus (Rh) testing and prophylaxis for first-trimester vaginal bleeding in the ambulatory setting. STUDY DESIGN: We used time-driven, activity-based costing to analyze tasks associated with Rh testing and prophylaxis of first-trimester vaginal bleeding at one hospital-based outpatient and two independent reproductive health clinics. At each site, we observed 10 patients undergoing Rh-typing and two patients undergoing Rh prophylaxis. We computed the costs of blood Rh-typing by both fingerstick and phlebotomy, cost of locating previous blood type in the electronic health record (available for 69.8% of hospital-based patients), and costs associated with Rh immune globulin prophylaxis. All costs are reported in 2021 US dollars. RESULTS: The hospital-based clinic reviewed the electronic health record to confirm Rh-status (cost, $26.18 per patient) and performed a phlebotomy, at $47.11 per patient, if none was recorded. The independent clinics typed blood by fingerstick, at a per-patient cost of $4.07. Rh-immune globulin administration costs, including the medication, were similar across facilities, at a mean of $145.66 per patient. Projected yearly costs for testing and prophylaxis were $55,831 for the hospital-based clinic, which was the lowest-volume site, $47,941 for Clinic A, which saw 150 patients/month, and $185,654 for Clinic B, which saw 600 patients/month. CONCLUSIONS: Rh testing and prophylaxis for first-trimester vaginal bleeding generates considerable costs for outpatient facilities, even for Rh-positive patients with a prior blood type on record. IMPLICATIONS: Rh testing and prophylaxis for first-trimester bleeding generate considerable costs even for Rh-positive patients and those with a previously known blood type. These findings highlight the need to reconsider this practice, which is no longer supported by evidence and already safely waived in multiple medical settings in the United States and around the world.

Rh immune globulin immunoprophylaxis after RhD-positive red cell exposure in RhD-negative patients via transfusion: A survey of practices.

BACKGROUND: Current Association for the Advancement of Blood & Biotherapies (AABB) standards require transfusion services to have a policy on Rh immune globulin (RhIG) immunoprophylaxis for when RhD-negative patients are exposed to RhD-positive red cells. This is a survey of AABB-accredited transfusion services in the United States (US) regarding institutional policies and practices on RhIG immunoprophylaxis after RhD-negative patients receive RhD-positive (i.e., RhD-incompatible) packed red blood cell (pRBC) and platelet transfusions. RESULTS: Approximately half of the respondents (50.4%, 116/230) have policies on RhIG administration after RhD-incompatible pRBC and platelet transfusions, while others had policies for only pRBC (13.5%, 31/230) or only platelet (17.8%, 41/230) transfusions, but not both. In contrast, 18.3% (42/230) report that their institution has no written policies on RhIG immunoprophylaxis after RhD-incompatible transfusions. Most institutions (70.2%, 99/141) do not have policies addressing safety parameters to mitigate the risk of hemolysis associated with the high dose of RhIG required to prevent RhD alloimmunization after RhD-incompatible pRBC transfusions. DISCUSSION: With approximately half of US AABB-accredited institutions report having policies on RhIG immunoprophylaxis after both RhD-incompatible pRBC and platelet transfusions, some institutions may not be in compliance with AABB standards. Further, most with policies on RhIG immunoprophylaxis after RhD-incompatible pRBC transfusion do not have written safeguards to mitigate the risk of hemolysis associated with the high dose of RhIG required. CONCLUSION: This survey underscores the diverse and inadequate institutional policies on RhIG immunoprophylaxis after RhD exposure in Rh-negative patients via transfusion. This observation identifies an opportunity to improve transfusion safety.

Guideline No. 448: Prevention of Rh D Alloimmunization.

OBJECTIVE: This guideline provides recommendations for the prevention of Rh D alloimmunization (isoimmunization) in pregnancy, including parental testing, routine postpartum and antepartum prophylaxis, and other clinical indications for prophylaxis. Prevention of red cell alloimmunization in pregnancy with atypical antigens (other than the D antigen), for which immunoprophylaxis is not currently available, is not addressed in this guideline. TARGET POPULATION: All Rh D-negative pregnant individuals at risk for Rh D alloimmunization due to potential exposure to a paternally derived fetal Rh D antigen. OUTCOMES: Routine postpartum and antepartum Rh D immunoprophylaxis reduces the risk of Rh D alloimmunization at 6 months postpartum and in a subsequent pregnancy. BENEFITS, HARMS, AND COSTS: This guideline details the population of pregnant individuals who may benefit from Rho(D) immune globulin (RhIG) immunoprophylaxis. Thus, those for whom the intervention is not required may avoid adverse effects, while those who are at risk of alloimmunization may mitigate this risk for themselves and/or their fetus. EVIDENCE: For recommendations regarding use of RhIG, Medline and Medline in Process via Ovid and Embase Classic + Embase via Ovid were searched using both the trials and observational studies search strategies with study design filters. For trials, the Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Database of Abstracts of Reviews of Effects via Ovid were also searched. All databases were searched from January 2000 to November 26, 2019. Studies published before 2000 were captured from the grey literature of national obstetrics and gynaecology specialty societies, luminary specialty journals, and bibliographic searching. A formal process for the systematic review was undertaken for this update, as described in the systematic review manuscript published separately. VALIDATION METHODS: The authors rated the quality of evidence and strength of recommendations using the SOGC's modified GRADE approach. See Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations). INTENDED AUDIENCE: The intended users of this guideline include prenatal care providers such as obstetricians, midwives, family physicians, emergency room physicians, and residents, as well as registered nurses and nurse practitioners. TWEETABLE ABSTRACT: An updated Canadian guideline for prevention of Rh D alloimmunization addresses D variants, cffDNA for fetal Rh type, and updates recommendations on timing of RhIG administration. SUMMARY STATEMENTS: RECOMMENDATIONS.

[Prevention of Rh D alloimmunization in the first trimester of the pregnancy: French College of Obstetricians and Gynecologists guidelines for clinical practice]. / Prévention de l'allo-immunisation anti-RH1 au premier trimestre de la grossesse : recommandations pour la pratique clinique du Collège national des gynécologues-obstétriciens français.

OBJECTIVE: To provide recommendations for the prevention of Rh D alloimmunization in the first trimester of pregnancy. MATERIALS AND METHODS: The quality of evidence of the literature was assessed following the GRADE methodology with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on Pubmed, Cochrane, EMBASE, and Google Scholar databases. The quality of evidence was assessed (high, moderate, low, very low) and a recommendation was formulated: (i) strong, (ii) weak, or (iii) no recommendation. The recommendations were reviewed in two rounds with reviewers from the scientific board of the French College of the OB/GYN (Delphi survey) to select the consensus recommendations. RESULTS: The three recommendations from PICO questions reached agreement using the Delphi method. It is recommended not to administer Rh D immunoglobulin before 12 weeks of gestation to reduce the risk of alloimmunization in case of abortion or miscarriage, in RhD negative patients when the genitor is RhD positive or unknown (Weak recommendation. Very low-quality evidence). It is recommended not to administer Rh D immunoglobulin before 12 weeks of gestation to reduce the risk of alloimmunization in cases of bleeding in an ongoing intrauterine pregnancy (Weak recommendation. Very low-quality evidence). The literature data are insufficient in quality and quantity to determine if the injection of Rh D immunoglobulin reduces the risk of alloimmunization in the case of an ectopic pregnancy (No recommendation. Very low-quality evidence). CONCLUSION: Even though the quality of evidence from the studies is very low, it is recommended not to administer Rh D immunoglobulin in case of abortion, miscarriage or bleeding before 12 weeks of amenorrhea. The quality of evidence was too low to issue a recommendation regarding ectopic pregnancy.

Guide to Rho(D) Immune Globulin in Women With Molecularly Defined Asian-type DEL (c.1227G>A).

Rh hemolytic disease of the fetus and newborn is a potential risk for D-negative mothers who produce anti-D during pregnancy, which can lead to morbidity and mortality in subsequent pregnancies. To prevent this hemolytic disease, Rho(D) immune globulin (RhIG) is generally administered to D-negative mothers without anti-D at 28 weeks of gestation and shortly after delivery. However, current guidelines suggest that pregnant mothers with molecularly defined weak D types 1, 2, 3, 4.0, and 4.1 do not need RhIG as they are unlikely to produce alloanti-D when exposed to fetuses with D-positive red cells. This issue and the necessity of RHD genotyping have been extensively discussed in Western countries, where these variants are relatively common. Recent evidence indicates that women with Asian-type DEL (c.1227G>A) also do not form alloanti-D when exposed to D-positive red cells. We report that mothers with molecularly defined Asian-type DEL, similar to those with weak D types 1, 2, 3, 4.0, and 4.1, do not require RhIG before and after delivery. Collectively, this review could pave the way for the revision of international guidelines to include the selective use of RhIG based on specific genotypes, particularly in women with the Asian-type DEL.

Reconsidering Routine Repeat Group and Screens During Pregnancy-Personalizing Pregnancy Care.

The group and screen (G&S) are performed in early pregnancy to identify clinically significant antibodies (CSA) that may necessitate fetal monitoring for hemolysis/anemia or affect RhIg eligibility. Guidelines vary, including differences between RhD-positive and negative patients, but typically, the G&S is repeated at 28 weeks, and sometimes pre-delivery. We reviewed data showing a low risk (0.01%-0.43%) of detecting a new CSA in late gestation (late alloimmunization) and the risk of late alloimmunization causing severe hemolysis/anemia is even lower at <0.01%. Routinely repeating a G&S at 28 weeks and delivery may not be necessary for healthy, low-risk pregnancies.

Prevention of Rhesus-D Alloimmunization in the First Trimester of Pregnancy: Economic Analysis of Three Management Strategies.

Anti-D alloimmunization in the first trimester of pregnancy has long been the subject of prevention with anti-D immunoglobulins during events at risk of fetomaternal hemorrhage. Although the efficacy of preventing anti-D alloimmunization by an injection of immunoglobulin at 28 weeks of gestation (WG) is obvious, the literature provides little evidence of the effectiveness before 12+6 WG and several countries have modified their recommendations. In the presumed absence of a difference in alloimmunization risk between early and late prevention, our objective was to evaluate and compare the cost of treatment for 3 alloimmunization prevention strategies in France, the United Kingdom, and the Netherlands. This was a single-center retrospective study. Our target population included all women who received anti-D immunoglobulins (Rhophylac) in the first trimester of pregnancy before 12+6 WG at Nantes University Hospital in 2018 (N = 356). Within the target population, 2 other populations were constituted based on British (N = 145) and Dutch (N = 142) clinical practice guidelines (CPG). These 3 populations were analyzed for the comparative cost of treatment for prevention from a health system perspective. The average cost of Rhophylac alloimmunization prevention for 1 episode was €117.8 from a health system perspective. The total cost attributed to prevention in 2018 at Nantes University Hospital (N = 356) was €41,931.4 according to this perspective. If the UK CPG or Dutch CPG had been applied to the Nantes target population, a saving of around 60% would have been achieved. At the national level, the cost according to the health system perspective specifically attributable to induced abortion (N estimated = 26,916) could represent a total cost of €3,170,704. This study highlighted the high cost of the French prevention strategy in the first trimester of pregnancy compared with British or Dutch strategies. The modification of our practices would allow substantial financial savings to the French health system but would also avoid the nonrecommended exposure to a blood product at this term, would allow a faster medical management and a relief of the care system.

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

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 2017-2020 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 seven false-negative (0.04%) results. Sensitivity of the assays was 99.93%, while specificity was 99.24%. CONCLUSION: Few false-negative results support the good analysis quality of fetal RHD genotyping. Routine cord blood RhD typing will therefore be discontinued nationwide and postnatal anti-D Ig will now be given based on the result of fetal RHD genotyping.

Rh(D) immune globulin administration in pregnancy: Retrospective audit of patient safety events followed by targeted educational intervention with Bayesian analysis.

OBJECTIVES: To examine local patient safety events related to the administration of anti-Rh(D) immune globin (RhIG) during pregnancy, and to follow-up with targeted educational intervention to improve knowledge of this process. BACKGROUND: Administration RhIG is established treatment for the prevention of haemolytic disease of the foetus and newborn (HDFN). However, patient safety events in relation to its correct use continue to occur. METHODS: A retrospective audit of patient safety events related to RhIG administration during pregnancy was performed. Targeted educational intervention in the form of PowerPoint® presentation were given to nursing staff, laboratory staff and physicians and evaluated with pre- and post-tests using multiple-choice questions given immediately before and after the presentation. RESULTS: An annual incidence of 0.24% of patient safety events related to the administration of RhIG during pregnancy was found. These events were mostly in the preanalytical phase, for example mislabelled samples or samples for D-rosette/Kleihauer-Betke testing drawn from the baby, not the mother. Using Bayesian analysis, the probability of positive effect for the targeted educational intervention was 100% with a median improved score of 29%. This was compared with a control group using standard curriculum education intervention based on the current curriculum for nursing, laboratory and medical students which showed a median improved score of only 4.4%. CONCLUSIONS: Administration of RhIG during pregnancy is a multistep process involving health care professionals of several disciplines providing opportunities to enhance the curriculum for nursing, laboratory and medical students and to ensure on-going education.

Fetal-maternal incompatibility in the Rh system. Rh isoimmunization associated with hereditary spherocytosis: case presentation and review of the literature.

Next to A and B antigens, agglutinogen D exhibits the highest immunogenicity. Following the transfusion of D-positive red blood cells (RBCs), almost 80% of D-negative recipients develop anti-D antibodies (Abs). Subsequently, anti-D immunization further promotes the synthesis of Abs towards other blood group antigens in or outside the Rh system. The D antigen is also involved in 95% of cases of hemolytic disease of the newborn. Transfusions, hemotherapy, grafts, and obstetric history (abortions, ectopic pregnancy, births) are all risk factors for Rh isoimmunization. In the case of ABO compatibility between mother and fetus, Rh-positive fetal RBCs that have reached the maternal bloodstream are not destroyed by group agglutinins, and Rh antigenic sites are not hidden by the maternal immune system. But a Rh-negative mother with a homozygous Rh-positive husband will certainly have a Rh-positive fetus. As it has an irreversible evolution, the Rh isoimmunization once installed cannot be influenced in the sense of decreasing the Ab titer, therefore, injectable globulin has no effect. A particular case was that of a newborn with Rh system incompatibility associated with hereditary spherocytosis The clinical balance at birth reflects the severe jaundice of the female newborn of 3140 g, gestational age 38∕39 weeks, extracted by lower-segment transverse Caesarean section, with a double loop nuchal cord, Apgar score 8. Because the jaundice was severe and atypical (face and upper chest), we considered the possibility of coexistence of hemolytic disease of the newborn by Rh blood group incompatibility associated with hereditary spherocytosis, as it turned out to be true and mentioned. Changes in genes encoding proteins in the structure of the RBC membrane have amplified hemolysis induced by maternal-fetal isoimmunization in the Rh system. Massive hemolysis accentuated by congenital spherocytosis, confirmed later, imposed blood transfusion and dynamic monitoring.

Society of Family Planning committee consensus on Rh testing in early pregnancy.

Historical evidence that fetal red blood cell (RBC) exposure during early spontaneous or induced abortion can cause maternal Rh sensitization is limited. A close reading of these studies indicates that forgoing Rh immunoglobulin administration before 12weeks gestation is highly unlikely to increase risk of Rh (D) antibody development, and recent studies indicate that fetal RBC exposure during aspiration abortion <12 weeks gestation is below the calculated threshold to cause maternal Rh sensitization, and the amount of fetomaternal hemorrhage during dilation and evacuation procedures up to 18weeks gestation is adequately treated with 100mcg of Rh immunoglobulin. We provide updated recommendations for Rh immunoglobulin administration based on this new evidence.

Following targeted routine antenatal anti-D prophylaxis, almost half of the pregnant women had undetectable anti-D prophylaxis at delivery.

INTRODUCTION: In September 2016, a nationwide targeted routine antenatal anti-D prophylaxis program was implemented in Norway. The prophylaxis (anti-D immunoglobulin) aims to cover the whole third trimester and is administered in gestational week 28 to RhD-negative women who carry RhD-positive fetuses. However, in many women, antibody screening at delivery does not detect anti-D immunoglobulin. The goal of this study was to investigate the presumable role of dose and timing of antenatal anti-D immunoglobulin administration in non-detectable prophylaxis at the time of delivery. MATERIAL AND METHODS: In this retrospective observational study, RhD-negative pregnant women who gave birth at Oslo University Hospital and Akershus University Hospital between January 2017 and December 2019 were analyzed. Women who received antenatal anti-D immunoglobulin (1500 IU at Oslo University Hospital and 1250 IU at Akershus University Hospital) when fetal RHD genotyping at gestational week 24 predicted an RhD-positive fetus were included if an antibody screen at delivery was available. Data from the blood bank, maternity information systems, and electronic patient records were used. RESULTS: Analysis of the 984 RhD-negative women at the two hospitals revealed that 45.4% had non-detectable anti-D at delivery. A significant difference between the two hospitals was observed: 40.5% at Oslo University Hospital (n = 509) and 50.7% at Akershus University Hospital (n = 475) (p = 0.001). The proportion with non-detectable anti-D increased to 56.0 and 75.3%, respectively (p = 0.008) in the group of women who gave birth 12 weeks after routine antenatal anti-D prophylaxis. Significantly fewer women had detectable anti-D at delivery when the lower anti-D immunoglobulin dose (1250 IU) was administered antenatally. Multiple logistic regression indicated that the time interval between routine antenatal anti-D prophylaxis and delivery, in addition to anti-D dose, were significantly associated with detectable anti-D at delivery (p < 0.001). CONCLUSIONS: We do not know which RhD-negative pregnant women, despite antenatal anti-D prophylaxis, are at risk of RhD alloimmunization, when antibody screening is negative at delivery. Administration of antenatal prophylaxis should probably be moved closer to delivery, since the risk of fetomaternal hemorrhage is higher during the last weeks of the third trimester.

Cost-effectiveness of noninvasive fetal RhD blood group genotyping in nonalloimmunized and alloimmunized pregnancies.

BACKGROUND: We sought to determine the cost-effectiveness of noninvasive fetal RhD blood group genotyping in nonalloimmunized and alloimmunized pregnancies in Canada. STUDY DESIGN AND METHODS: We developed two probabilistic state-transition (Markov) microsimulation models to compare fetal genotyping followed by targeted management versus usual care (i.e., universal Rh immunoglobulin [RhIG] prophylaxis in nonalloimmunized RhD-negative pregnancies, or universal intensive monitoring in alloimmunized pregnancies). The reference case considered a healthcare payer perspective and a 10-year time horizon. Sensitivity analysis examined assumptions related to test cost, paternal screening, subsequent pregnancies, other alloantibodies (e.g., K, Rh c/C/E), societal perspective, and lifetime horizon. RESULTS: Fetal genotyping in nonalloimmunized pregnancies (at per-sample test cost of C$247/US$311) was associated with a slightly higher probability of maternal alloimmunization (22 vs. 21 per 10,000) and a reduced number of RhIG injections (1.427 vs. 1.795) than usual care. It was more expensive (C$154/US$194, 95% Credible Interval [CrI]: C$139/US$175-C$169/US$213) and had little impact on QALYs (0.0007, 95%CrI: -0.01-0.01). These results were sensitive to the test cost (threshold achieved at C$88/US$111), and inclusion of paternal screening. Fetal genotyping in alloimmunized pregnancies (at test cost of C$328/US$413) was less expensive (-C$6280/US$7903, 95% CrI: -C$6325/US$7959 to -C$6229/US$7838) and more effective (0.19 QALYs, 95% CrI 0.17-0.20) than usual care. These cost savings remained robust in sensitivity analyses. DISCUSSION: Noninvasive fetal RhD genotyping saves resources and represents good value for the management of alloimmunized pregnancies. If the cost of genotyping is substantially decreased, the targeted intervention can become a viable option for nonalloimmunized pregnancies.

Risk factors for RhD immunisation in a high coverage prevention programme of antenatal and postnatal RhIg: a nationwide cohort study.

OBJECTIVE: To evaluate which risk factors for RhD immunisation remain, despite adequate routine antenatal and postnatal RhIg prophylaxis (1000 IU RhIg) and additional administration of RhIg. The second objective was assessment of the current prevalence of RhD immunisations. DESIGN: Prospective cohort study. SETTING: The Netherlands. POPULATION: Two-year nationwide cohort of alloimmunised RhD-negative women. METHODS: RhD-negative women in their first RhD immunised pregnancy were included for risk factor analysis. We compared risk factors for RhD immunisation, occurring either in the previous non-immunised pregnancy or in the index pregnancy, with national population data derived from the Dutch perinatal registration (Perined). RESULTS: In the 2-year cohort, data from 193 women were eligible for analysis. Significant risk factors in women previously experiencing a pregnancy of an RhD-positive child (n = 113) were: caesarean section (CS) (OR 1.7, 95% CI 1.1-2.6), perinatal death (OR 3.5, 95% CI 1.1-10.9), gestational age >42 weeks (OR 6.1, 95% CI 2.2-16.6), postnatal bleeding (>1000 ml) (OR 2.0, 95% CI 1.1-3.6), manual removal of the placenta (MRP) (OR 4.3, 95% CI 2.0-9.3); these factors often occurred in combination. The miscarriage rate was significantly higher than in the Dutch population (35% versus 12.-5%, P < 0.001). CONCLUSION: Complicated deliveries, including cases of major bleeding and surgical interventions (CS, MRP), must be recognised as a risk factor, requiring estimation of fetomaternal haemorrhage volume and adjustment of RhIg dosing. The higher miscarriage rate suggests that existing RhIg protocols need adjustment or better compliance. TWEETABLE ABSTRACT: Complicated delivery (caesarean section, manual removal placenta, major bleeding) is the most valid risk factor for RhD immunization despite antenatal and postnatal RhIg.

Practices for RhD alloimmunization prevention: a vignette-based survey of midwives.

INTRODUCTION: Despite the availability guidelines to prevent RhD alloimmunization, severe hemolytic disease of fetus and newborn still occurs in high-income countries. The aim of the study was (1) To assess variations in practices for the prevention of RhD alloimmunization, and (2) to understand midwives' acceptance and appropriation of fetal RhD genotyping. METHODS: Descriptive cross-sectional survey of French midwives from September 2017 through January 2018. Participants were asked to complete an internet-based questionnaire that included three clinical vignettes. They were questioned about their practices concerning early pregnancy visit by RhD-negative women, prevention of RhD alloimmunization in women with second-trimester metrorrhagia, and RhD fetal genotyping. RESULTS: A total of 827 midwives completed the questionnaire. Only 21.1% reported that they practice all the preventive measures recommended in early pregnancy. In a situation at high risk of RhD alloimmunization during pregnancy, 97.2% of midwives would perform immunoprophylaxis. Nearly, all midwives reported providing information about RhD alloimmunization (92.4%) at the beginning of pregnancy, although only 11.3% offered both written and verbal information; at the time of systematic anti-D immunoprophylaxis (28 weeks), 78% provided information, but only 2.7% both verbally and in writing. Finally, only 50.8% of midwives preferred to include RhD fetal genotyping in routine prenatal prophylaxis. DISCUSSION: This study showed significant variations in French midwives' practices to prevent RhD alloimmunization. Better dissemination of guidelines is needed to improve both consistent use of these practices and the quality of information delivered to RhD-negative pregnant women.