Perinatal survival and procedure-related complications after intrauterine transfusion for red cell alloimmunization

Effective management of foetal anaemia in Rh(D) alloimmunised pregnant women with intrauterine transfusion: a Systematic Review

BACKGROUND

Foetal anaemia is caused by a severe pregnancy complication, haemolytic disease of the foetus and newborn. Intrauterine transfusions (IUTs) are performed to treat foetal anaemia in alloimmunised pregnant women. If left untreated hydrops can develop thereby reducing the chance of survival. Survival rates have improved but the procedure is not without complications. Procedure-related complications can be associated with early gestational age, hence delaying IUT could improve outcomes. This review aims to determine the effectiveness and safety of IUTs by examining survival and mortality rates, procedure-related complications with associated foetal mortality and the influence of hydrops.

STUDY DESIGN AND METHOD

A systematic review was conducted by searching keywords in four scientific databases from January 2000 to April 2022. A meta-analysis was performed with the OpenMeta-Analyst software using an arcsine transformed proportion with the binary random-effects model and maximum likelihood method.

RESULTS

Fifteen studies were identified as eligible and used in the meta-analysis. The forest plots all showed statistically significant outcomes with heterogeneity of data. Results indicated a greater foetal survival rate with IUT to treat anaemic foetuses, a low foetal mortality rate, and low risk of procedure-related complications associated with foetal loss but a higher risk of foetal mortality when hydrops is present.

CONCLUSION

The findings of this systematic review and meta-analysis provide evidence that IUT is a safe and effective treatment for foetal anaemia in the absence of hydrops when experienced personnel perform the procedure to minimise the risk of procedure-related complications.

Prevalence of unexpected red blood cell antibodies in pregnant women and follow-up of pregnancy outcome in pregnant women treated with intra-uterine transfusion

BACKGROUND

For the management of hemolytic disease of the fetus and newborn (HDFN), it is important to detect unexpected red cell antibody in pregnant women. We assessed the prevalence of unexpected red cell antibodies in consecutive pregnant women attending antenatal clinic (ANC). More importantly, cases with unexpected antibody causing severe anemia were followed-up for intervention (Intra-uterine transfusion {IUT}) and outcome of pregnancy (still-birth/live-healthy).

AIMS AND OBJECTIVES

The study was conducted with an objective to find the prevalence of unexpected RBC antibodies in pregnant women, their specificity and to do the follow-up for IUT and outcome of pregnancy (still-birth, live-birth) in antibody positive women.

MATERIALS AND METHODS

This was a prospective study from January 2021 to May 2022 at two tertiary care centres. All antenatal samples received by the laboratory were screened for unexpected red cell antibody. Whenever antibody screen was positive, antibody identification was performed. Patients, positive for unexpected antibody and anemia were followed up for any transfusion-based intervention and outcome of pregnancy.

RESULTS

A total of 539 consecutive samples were worked up and among these, 10 samples (1.85%) were found to be antibody positive. The antibodies identified were Anti-D (n=6), anti-Leb (n=1), anti-M (n=1), anti-C (n=1) and anti-E (n=1).The prevalence of unexpected antibodies in Rh positive and Rh negative pregnant women was 0.83% and 10.9% respectively. Follow-up was done for all 10 cases with unexpected antibody and anemia was monitored by MCA PSV (middle cerebral artery peak systolic velocity).Two women developed severe anemia thus requiring single intrauterine transfusion (at 26 weeks and 28 weeks respectively) each, for correction of anemia. In both these cases, healthy male child was delivered. At 3-month follow-up both children were alive and healthy.

CONCLUSION

The study found prevalence of unexpected RBC antibodies in pregnant women as 1.85%. The study also underlined importance of transfusion-based interventions contributing to successful outcome in couple of cases with severe anemia.

Intrauterine transfusion in hydropic fetuses: An outcome analysis

The objective of this study is to determine the perinatal outcome in pregnancies with hydropic fetuses. The study was a retrospective evaluation of data on intrauterine transfusion (IUT) done in hydropic fetuses for correction of severe anemia from December 2017 to August 2021 in AIIMS Jodhpur. The retrospective case series involves five cases that underwent IUT for severe fetal anemia. All had a sign of hydrops at the time of presentation. Out of five cases, four were of alloimmunized pregnancies while one was of hydrops fetalis secondary to parvovirus infection. The presence of severe hydrops at the time of presentation is a poor prognostic factor affecting fetal survival post-IUT therapy.

Hemolytic disease of the fetus and newborn: systematic literature review of the antenatal landscape

BACKGROUND

Prevention of pregnancy-related alloimmunization and the management of hemolytic disease of the fetus and newborn (HDFN) has significantly improved over the past decades. Considering improvements in HDFN care, the objectives of this systematic literature review were to assess the prenatal treatment landscape and outcomes of Rh(D)- and K-mediated HDFN in mothers and fetuses, to identify the burden of disease, to identify evidence gaps in the literature, and to provide recommendations for future research.

METHODS

We performed a systematic search on MEDLINE, EMBASE and clinicaltrials.gov. Observational studies, trials, modelling studies, systematic reviews of cohort studies, and case reports and series of women and/or their fetus with HDFN caused by Rhesus (Rh)D or Kell alloimmunization. Extracted data included prevalence; treatment patterns; clinical outcomes; treatment efficacy; and mortality.

RESULTS

We identified 2,541 articles. After excluding 2,482 articles and adding 1 article from screening systematic reviews, 60 articles were selected. Most abstracted data were from case reports and case series. Prevalence was 0.047% and 0.006% for Rh(D)- and K-mediated HDFN, respectively. Most commonly reported antenatal treatment was intrauterine transfusion (IUT; median frequency [interquartile range]: 13.0% [7.2-66.0]). Average gestational age at first IUT ranged between 25 and 27 weeks. weeks. This timing is early and carries risks, which were observed in outcomes associated with IUTs. The rate of hydrops fetalis among pregnancies with Rh(D)-mediated HDFN treated with IUT was 14.8% (range, 0-50%) and 39.2% in K-mediated HDFN. Overall mean ± SD fetal mortality rate that was found to be 19.8%±29.4% across 19 studies. Mean gestational age at birth ranged between 34 and 36 weeks.

CONCLUSION

These findings corroborate the rareness of HDFN and frequently needed intrauterine transfusion with inherent risks, and most births occur at a late preterm gestational age. We identified several evidence gaps providing opportunities for future studies.

Fetal and Neonatal Reticulocyte Count Response to Intrauterine Transfusion for the Treatment of Red Blood Cell Alloimmunization

Management of hemolytic disease of the fetus and newborn relies on monitoring of maternal antibody titers, fetal ultrasound, and fetal middle cerebral artery peak systolic velocity studies and is generally treated by intrauterine transfusion (IUT). Few studies have explored fetal and neonate physiological responses to IUT. Our objective was to examine fetal erythropoietic response and to examine neonatal erythropoietic effects after treatment. Thirty-six patients treated from 2005 to 2015 were identified retroactively. The time course of treatment, including gestational age and number of IUT, and timing of delivery were reviewed. Fetal reticulocyte count and neonatal hemoglobin and reticulocyte counts were analyzed for each IUT. For each gestational week, reticulocyte count decreased by ∼8.6% (95% confidence interval [CI]: 5.3-12.0). In the neonatal period, there was significant correlation between hemoglobin at birth and number of transfusions (Spearman correlation 0.473, 95% CI: 0.113-0.715, P =0.01) as well as reticulocyte count at birth and number of transfusions (Spearman correlation: 0.393, 95% CI: 0.058-0.642, P =0.02). IUT appears to have a direct and measurable effect on fetal reticulocyte production which persists in neonates.

Short-term outcomes following intrauterine transfusions for fetal anaemia: A retrospective cohort study

BACKGROUND

Intrauterine transfusion (IUT) is the accepted standard for management of severe fetal anaemia. However, fetal transfusion may be associated with procedural complications such as fetal demise. There is a paucity of recent data on outcomes for severe fetal anaemia in Australia as compared with published outcomes from large international centres.

AIMS

To review the indications for and the procedural, obstetric and neonatal outcomes following intrauterine transfusion for fetal anaemia conducted at the New South Wales Fetal Therapy Centre (NSW FTC).

MATERIALS AND METHODS

Retrospective cohort study conducted between 2005 and 2017 of the outcomes of 85 IUT procedures (39 pregnancies). Data collected included maternal demographics, procedural and obstetric details and short-term neonatal outcomes.

RESULTS

Complete outcome data were available for 36/39 pregnancies. Red cell antibodies were the main indication for fetal transfusion (79%, predominantly D, Kell and other Rhesus antibodies) with parvovirus accounting for 8% of procedures. IUT was associated with a pregnancy loss rate of 1.2%/procedure, amounting to 2.6%/pregnancy. Fetal losses were limited to those complicated by hydrops prior to IUT (3/10 hydrops vs 0/26 non-hydropic; P = 0.003).

CONCLUSIONS

Procedural outcomes at NSW FTC compare favourably with international centres (1.1-8.7% procedural loss rate). However, this comparison is limited, as no procedures were performed during the last 24 months of the study. Given this, a nationwide audit is recommended to help guide appropriate centralisation of procedures and thereby maximise clinician experience and outcome.

Red cell alloimmunization: A 2020 update

Management of maternal red cell alloimmunization has been revolutionized over the last 60 years. Advances in the prevention, screening, diagnosis, and treatment of alloimmune-induced fetal anemia make this condition an exemplar for contemporary practice in fetal therapy. Since survival is now an expectation, attention has turned to optimization of long-term outcomes following an alloimmunized pregnancy. In this review, the current management of red cell alloimmunization is described. Current research and future directions are discussed with particular emphasis on later life outcomes after alloimmune fetal anemia.

NT-proBNP: A Useful Biochemical Marker for Prognosis in Rh-Isoimmunized Pregnancies

BACKGROUND

Rh incompatibility sometimes results in life-threatening conditions in fetus like severe anemia and jaundice, leading to kernicterus and even death. Even after an uneventful intrauterine transfusion (IUT), fetus may not survive despite correction of the fetal anemia. Finding appropriate markers may help in determining the prognosis of such cases. The N-terminal prohormone of brain natriuretic peptide (NT-proBNP) suggests some degree of heart failure.

OBJECTIVE

Present study was planned to evaluate its role in predicting the outcome of fetus in Rh-isoimmunized pregnant woman.

METHODS

This prospective study consisted of total 40 pregnant patients: 10 pregnant Rh-isoimmunized women with hydropic fetuses, 10 with non-hydropic fetuses and 20 control group. If the MCA-PSV was > 1.5 MOM, cord blood sampling and IUT was done and sent for fetal hematocrit and NT-proBNP.

RESULTS

The levels of NT-proBNP at various periods of gestation in hydropic, non-hydropic and control group fetuses showed positive correlation with the degree of fetal anemia.

CONCLUSION

Correlation of high levels of NT-proBNP to fetal anemia proves that hydrops fetalis is probably due to progressive high cardiac output myocardial failure, increased capillary permeability and perhaps reduced coronary flow.

Perinatal outcomes of intrauterine transfusion for foetal anaemia due to red blood cell alloimmunisation

The aim of this study was to evaluate the maternal and neonatal outcomes of patients who underwent intrauterine transfusion (IUT) for foetal anaemia due to red blood cell alloimmunisation and to determine the factors that affected the outcomes. All pregnancies that were treated with IUT due to Rh immunisation between January 2015 and June 2018 in the Kanuni Sultan Süleyman Training and Research Hospital, Department of Obstetrics and Gynaecology, were evaluated retrospectively. IUT due to non-Rh alloimmunisation, parvovirus B19 infection, chronic fetomaternal haemorrhage and foetal anaemia due to homozygous alpha-thalassemia were not included in the study. The perinatal and neonatal outcomes of the patients were retrospectively analysed. The gestational age, ultrasonography findings before and after IUT, laboratory results, complications related to IUT, and data on the newborns were recorded. The cases were divided into two groups, those with complication and those without complications, and their perinatal outcomes were compared. A total of 110 IUTs were performed in 42 foetuses. The survival rate after transfusion was 80.95%. Procedure-related complications were found in 12.7% of cases. There were no significant differences between the demographic and clinical characteristics of the patients with and without complications. The survival rate was lower and perinatal mortality was higher in foetuses with hydrops fetalis. IUT is a safe and effective procedure that can be used in the treatment of foetal anaemia in experienced centres. Survival rates can be increased by referring patients to experienced perinatology centres, by improving the IUT technique, and by reducing technique-related complications.Impact statementWhat is already known on this subject? The predominant use of IUT is to treat foetal anaemia due to red blood cell alloimmunisation. Despite the decrease after anti-D immune globulin prophylaxis, Rh immunisation is still a major cause of foetal anaemia. However, foetal survival rates have increased with the use of IUT.What do the results of this study add? The survival rates were increased after the development of a high-resolution ultrasound. Because foetal monitoring can be performed by ultrasonography, cord accidents and overload findings can be detected during transfusion, which allows for early interventions and increases survival rates.What are the implications of these findings for clinical practice and/or further research? The IUT procedure can be used in the treatment of foetal anaemia in experienced centres. After the technique was improved, the complication rates related to the procedure were decreased and foetal survival rates were increased. Further studies on the use of different IUT techniques will extend our findings.

Correlation of fetal blood vessel Doppler measurements with fetal anemia among Rhesus isoimmunized pregnancies after two intrauterine transfusions

OBJECTIVE

To assess the correlation between fetal blood vessel Doppler measurements and fetal anemia among Rhesus isoimmunized pregnancies after two intrauterine transfusions as a potential guide to therapy.

METHODS

A prospective observational study was conducted among 30 women who attended a single hospital in India between April 2, 2015 and October 30, 2016. The participants underwent a third intrauterine transfusion based on a middle cerebral artery (MCA) peak systolic velocity (PSV) of greater than 1.50 multiples of the median (MoM). Cordocentesis was performed before the third intrauterine transfusion and hematocrit values correlated with the blood vessel Doppler measurements.

RESULTS

The MCA PSV MoM and fetal hematocrit MoM had a correlation coefficient of -0.43 (95% confidence interval -0.68 to 0.08; P=0.017). The sensitivity, specificity, positive predictive value, and negative predictive value were 68%, 57%, 83%, and 33%, respectively. The descending aorta PSV δ and fetal hematocrit δ had a correlation coefficient of -0.54 (95% confidence interval -0.75 to -0.23; P=0.001). An area under the curve of 0.80 (standard error 0.085; P=0.017) had 87% sensitivity and 57% specificity for diagnosing fetal anemia.

CONCLUSION

The descending aorta PSV could offer a useful diagnostic adjunct to MCA PSV after two intrauterine transfusions.

Efficacy of Antenatal Intravenous Immunoglobulin Treatment in Pregnancies at High Risk due to Alloimmunization to Red Blood Cells

Background

Alloimmunization to red blood cells (RBCs) may result in fetal anemia prior to 20 weeks gestation. The question as to whether early commencement of antenatal treatment with high-dose intravenous immunoglobulins (IVIG) may prevent or at least delay the development of fetal anemia in the presence of alloantibodies to RBCs is highly relevant.

Patients and Results

Here we describe a patient with high-titer anti-K and two other severely affected pregnant women with a history of recurrent pregnancy loss due to high-titer anti-D or anti-D plus anti-C. Early commencement of treatment with IVIG (1 g/kg/week) resulted in prevention of intrauterine transfusion (IUT) in the former two cases, and in a significant delay of development of fetal anemia in the remaining case (26 weeks gestation).

Conclusion

Based on our findings and of previously published cases, early initiation of treatment of severely alloimmunized women with IVIG (1 g/kg/week) could potentially improve the outcome of fetuses at risk.

Does an intrauterine exchange transfusion improve the fetal prognosis in parvovirus infection cases?

BACKGROUND

Almost 20% of parvovirus B19 foetal infections require intrauterine transfusions. In addition, myocardial dysfunction has been observed in severe parvovirus B19 infections. One objective of an intrauterine exchange transfusion (IUET) is to avoid an overload during the transfusion. Our aim was to study the obstetrical and neonatal outcomes in cases of IUETs performed for foetal parvovirus infections and to compare our survival rate to those studies in which simple in utero transfusions were chosen.

STUDY DESIGN AND METHODS

This was a retrospective monocentre study of all patients followed up for parvovirus B19 infections in which IUETs were performed. An IUET was indicated when foetal hydrops was observed and/or when severe foetal anaemia was diagnosed though an elevation in the middle cerebral artery peak systolic velocity. The characteristics of each pregnancy and the neonatal outcomes were studied until hospital discharge.

RESULTS

Thirty-five IUETs were performed in 26 foetuses. The median gestational age of the first IUET was 22.6 weeks. Only one foetal bradycardia incidence was recorded during the procedure. Three medical pregnancy terminations were observed in our series, secondary to severe cerebral anomalies confirmed in the magnetic resonance imaging. Five in utero deaths occurred, in which 2 of the foetuses underwent multiple IUETs. All the neonates had normal haemoglobin levels at birth, and none were transferred to the neonatal intensive care unit. The overall survival rate was 70%.

CONCLUSION

IUETs exhibit a survival rate similar to that of simple intrauterine transfusions in foetal parvovirus infection cases.

The near disappearance of fetal hydrops in relation to current state-of-the-art management of red cell alloimmunization

Objective

In this study, we aim to evaluate trends in the condition of fetuses and neonates with hemolytic disease at the time of first intrauterine transfusion (IUT) and at birth, in relation to routine first‐trimester antibody screening, referral guidelines, and centralization of fetal therapy.

Method

We conducted a 30‐year cohort study including all women and fetuses treated with IUT for red cell alloimmunization at the Dutch national referral center for fetal therapy.

Results

Six hundred forty‐five fetuses received 1852 transfusions between 1 January 1987 and 31 December 2016. After the introduction of routine first‐trimester antibody screening, the hydrops rate declined from 39% to 15% (OR 0.284, 95% CI, 0.19‐0.42, P < 0.001). In the last time cohort, only one fetus presented with severe hydrops (OR 0.482, 95% CI, 0.38‐0.62, P < 0.001). Infants are born less often <32 weeks (OR 0.572, 95% CI, 0.39‐0.83, P = 0.004) and with higher neonatal hemoglobin (P < 0.001). Neonatal hemoglobin was positively independently associated with gestational age at birth, fetal hemoglobin, and additional intraperitoneal transfusion at last IUT.

Conclusion

Severe alloimmune hydrops, a formerly often lethal condition, has practically disappeared, most likely as a result of the introduction of routine early alloantibody screening, use of national guidelines, and pooling of expertise in national reference laboratories and a referral center for fetal therapy.

What's already known about this topic?

Severe alloimmune hydrops is associated with impaired outcome on both the short term and the long term.

What does this study add?

With routine early alloantibody screening, national guidelines, and pooling of expertise in national reference laboratories and a referral center for fetal therapy, severe alloimmune hydrops has almost disappeared.

Survival of hydrops cases no longer differs from hemolytic disease of the fetus and newborn cases without hydrops.

Children treated with intrauterine transfusions are now in better condition at birth.

Red Blood Cell Alloimmunization in the Pregnant Patient

Alloimmunization to red blood cell (RBC) antigens represents a challenge for physicians caring for women of child bearing potential. Exposure to non-self RBC antigens may occur during transfusion or pregnancy leading to the development of antibodies. If a subsequent fetus bears that antigen, maternal antibodies may attack the fetal red blood cells causing red cell destruction and clinically significant hemolytic disease of the fetus and newborn (HDFN). In the most severe cases, HDFN may result in intrauterine fetal demise due to high output cardiac failure, effusions and ascites, known as "hydrops fetalis". This article reviews strategies for management and prevention of RBC alloimmunization in women of child bearing potential.

Perinatal Outcome After Intrauterine Transfusion in Rh Isoimmunized Mothers

Objective

The objective of the study was to assess the fetal outcome after receiving intrauterine transfusion (IUT) in Rh-isoimmunized pregnancy in a tertiary care center.

Study Design

This was a retrospective observational descriptive study in which all Rh-negative gravidas with isoimmunization warranting IUTs (40 patients) were analyzed during the period from January 1, 2010 to October 31, 2015. Primary outcome variables were fetal outcomes and procedural-related factors.

Results

Forty pregnancies (13-hydropic, 27-non-hydropic) required 74 IUTs. IUT was performed at gestational age of 15.4-33 weeks when indicated. The amount of blood transfused ranged from 4 to 110 ml. There were two sudden intrauterine fetal deaths during the procedure, four post-procedure intrauterine fetal deaths in fetuses with severe hydrops, and three neonatal deaths. The overall survival rate was found to be 77.5%.

Conclusion

IUT was found to be an effective therapy in correcting anemia in fetuses of Rh isoimmunized mothers. Early diagnosis of fetal anemia and intrauterine blood transfusion by an experienced fetal medicine specialist is very important for the perinatal outcome.

Sonographic Demonstration of Intracranial Hemorrhage in a Fetus with Hydrops Fetalis due to Rh Alloimmunization after Intrauterine Intravascular Transfusion: A Case Report and Review of the Literature

Intrauterine transfusion is the most common and successful intrauterine procedure for the treatment of fetal anemia due to red cell alloimmunization. Fetal intracranial hemorrhage is a very rare complication of intrauterine transfusion in patients with Rh(D) alloimmunization and it has been demonstrated only in a few case reports in the literature. Herein, we described a case of grade IV intraventricular hemorrhage that was diagnosed following the first intrauterine transfusion and reviewed the literature about the fetal intracranial hemorrhage that occurred after intrauterine intravascular transfusion procedure.

Intrauterine Fetal Blood Transfusion: Descriptive study of the first four years' experience in Oman

OBJECTIVES

Haemolytic disease of the fetus and newborn (HDFN) causes hydrops fetalis. The successful treatment of HDFN has been reported with intrauterine blood transfusion (IUT). This study aimed to describe the initial experience with IUT procedures in Oman.

METHODS

This retrospective observational study took place at the Royal Hospital and Sultan Qaboos University Hospital Blood Bank, Muscat, Oman, and included all women who underwent IUT procedures in Oman between March 2012 and March 2016. Gestational and neonatal outcomes were assessed, including complications, morbidity, neurodevelopmental sequelae and mortality.

RESULTS

A total of 28 IUT procedures for 13 fetuses carried by 11 women were performed. Gestational age at the time of referral ranged from 13-30 weeks, while the median gestational age at first IUT procedure was 26 weeks (range: 19-30 weeks). Indications for the procedure included HDFN caused by anti-D (n = 6), a combination of anti-D and anti-C (n = 4), anti-K (n = 1) and anti-Jsb (n = 1) antibodies and nonimmune hydrops fetalis due to a congenital parvovirus infection (n = 1). Median fetal haemoglobin levels at the beginning and end of the procedure were 4.6 g/dL and 12.8 g/dL, respectively. Most procedures were transplacental intravascular transfusions through the placental umbilical cord root (71.4%), followed by transamniotic intravascular transfusions (14.3%). The overall survival rate was 61.5%, with five deaths; of these, four were intrauterine and one was an early neonatal death due to non-resolved hydrops and severe cardiac dysfunction.

CONCLUSION

As a relatively novel obstetric procedure in Oman, IUT seems to result in a favourable outcome for hydropic fetuses.

[Outcome of in utero transfusion in case of fœtomaternal red blood cell incompatibility]

OBJECTIVE

Erythrocyte allo-immunization's rate has decreased but without adapted treatment the prognosis is still poor. The aim of our study was to evaluate the fetal prognosis, the complication's rate and the risk factors of complications of the intrauterine transfusion.

METHODS

Retrospective study about 37 fetus and 86 intrauterine transfusions between 2001 and 2017. Our main criterion in judging was the occurrence of procedure related complications: premature membrane rupture or premature delivery within seven days from the procedure, chorioamnionitis, abnormal fetal heart rate indicating an emergency ceasarean section within the 24hours from the procedure, in utero death or neonatal death related to the procedure.

RESULTS

The survival rate was about 88.9% with a severe complication's rate of 5.8% per intrauterine transfusion and 13.5% per pregnancy. Intrauterine transfusions before 18 weeks of pregnancies was a complication risk factor: 50% of complications before 18 weeks vs. 1.3%, P=0.8×10^-3. On the contrary, hydrops did not seem to be a complication risk factor (16.7% of complication with hydrops vs. 3.9%, P=0.27). The localisation of the needle insertion, intra-abdominal or placental insertion, had no effect on the fetal prognosis.

CONCLUSION

Intrauterine transfusion complications are rare and it enhances the fetal prognosis. However, an early procedure is related to a higher rate of complications.