Increased perinatal loss after intrauterine transfusion for alloimmune anaemia before 20 weeks of gestation

Intravenous immunoglobulin for the treatment of severe maternal alloimmunization: individual patient data meta-analysis

OBJECTIVE

This study aimed to investigate the outcomes associated with the administration of maternal intravenous immunoglobulin in high-risk red blood cell-alloimmunized pregnancies.

DATA SOURCES

Medline, Embase, and Cochrane Library were systematically searched until June 2023.

STUDY ELIGIBILITY CRITERIA

This review included studies reporting on pregnancies with severe red blood cell alloimmunization, defined as either a previous fetal or neonatal death or the need for intrauterine transfusion before 24 weeks of gestation in the previous pregnancy as a result of hemolytic disease of the fetus and newborn.

METHODS

Cases were pregnancies that received intravenous immunoglobulin, whereas controls did not. Individual patient data meta-analysis was performed using the Bayesian framework.

RESULTS

Individual patient data analysis included 8 studies consisting of 97 cases and 97 controls. Intravenous immunoglobulin was associated with prolonged delta gestational age at the first intrauterine transfusion (gestational age of current pregnancy - gestational age at previous pregnancy) (mean difference, 3.19 weeks; 95% credible interval, 1.28-5.05), prolonged gestational age at the first intrauterine transfusion (mean difference, 1.32 weeks; 95% credible interval, 0.08-2.50), reduced risk of fetal hydrops at the time of first intrauterine transfusion (incidence rate ratio, 0.19; 95% credible interval, 0.07-0.45), reduced risk of fetal demise (incidence rate ratio, 0.23; 95% credible interval, 0.10-0.47), higher chances of live birth at ≥28 weeks (incidence rate ratio, 1.88; 95% credible interval, 1.31-2.69;), higher chances of live birth at ≥32 weeks (incidence rate ratio, 1.93; 95% credible interval, 1.32-2.83), and higher chances of survival at birth (incidence rate ratio, 1.82; 95% credible interval, 1.30-2.61). There was no substantial difference in the number of intrauterine transfusions, hemoglobin level at birth, bilirubin level at birth, or survival at hospital discharge for live births.

CONCLUSION

Intravenous immunoglobulin treatment in pregnancies at risk of severe early hemolytic disease of the fetus and newborn seems to have a clinically relevant beneficial effect on the course and severity of the disease.

The role of measuring peak systolic velocity of the middle cerebral artery blood flow and anti-K1 titre during pregnancy to detect foetuses with severe anaemia, foetal hydrops, and the requirement of intrauterine transfusion: A systematic review and meta-analysis

The clinical manifestation of foetal anaemia caused by maternal Kell alloantibodies differs from that caused by non-Kell alloantibodies. Severe anaemia develops in the foetus in the early weeks of gestation; therefore, proper management and early intervention are important. A systematic review and meta-analysis was performed to determine whether the anti-K1 titre can determine the sequelae of Kell alloimmunised pregnancies. Prospective and retrospective cohort studies were used to conduct a systematic review following a comprehensive literature search, in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Studies were screened based on a defined set of inclusion and exclusion criteria. A total of 5143 potential articles were identified. Ten studies were used in the meta-analysis of pregnancy outcomes for a specific anti-K1 titre cut-off. The meta-analysis identified statistical significance for intrauterine transfusion (ARD: 0.351; 95 % CI: 0.593-0.109; p-value = 0.004), hydrops (ARD: 0.808; 95 % CI: 1.145-0.472; p-value <0.001), intrauterine foetal death (ARD: 0.938; 95 % CI:1.344 to -0.533; p-value <0.001) and intrauterine transfusion for Doppler middle cerebral artery >1.5 MoM (ARD: 0.381; 95 % CI:1.079 to -0.317; p-value = 0.285). It was concluded that there is no correlation between anti-K1 titre and Kell sensitised pregnancy outcomes, but monitoring the anti-K1 titre is important to manage the pregnancy and it helps clinicians determine the need for intrauterine transfusions. Doppler middle cerebral artery peak systolic velocity is strongly correlated with foetal anaemia and is an efficient routine method for determining the need for intrauterine transfusions in pregnancies affected by anti-K1.

Intravenous immunoglobulin treatment of congenital parvovirus B19 induced anemia - a case report

BACKGROUND

Parvovirus is a common childhood infection that could be very dangerous to the fetus, if pregnant women become infected. The spectrum of effects range from pure red blood cell aplasia with hydrops fetalis to meningoencephalitis, with many symptoms in between. Severe anemia in the setting of pure red blood cell aplasia is one of the more common effects that neonatal experience (if infected intrapartum), with the current gold standard treatment being intrauterine or postnatal packed red blood cell (PRBC) transfusions, yet intravenous immunoglobulin (IVIG) may be a superior treatment option.

CASE PRESENTATION

A preterm infant was born at 26th week of gestational age via emergency Cesarean section due to hydrops fetalis, with parvovirus B19 exposure one month prior. The infant tested positive for IgM antibodies against parvovirus B19. Among many other serious complications of both hydrops fetalis and premature delivery, the infant had severe unremitting anemia, and received many PRBC transfusion over the course of his 71-day-long neonatal intensive care unit stay. During a follow up appointments as outpatient, his blood tests showed persistent high copies of parvovirus B19. He was then supported with PRBC transfusions and treated with IVIG. After three doses of IVIG, the infant's parvovirus B19 viral copy numbers have dramatically reduced and the infant did not require any more PRBC transfusions.

CONCLUSIONS

IVIG infusion effectively treated the parvovirus B19 infection and restored erythropoiesis making the child transfusion independent. Furthermore, since IVIG is safe and readily crosses the placenta, further studies are needed to determine if IVIG should be considered as an alternative prenatal treatment for congenital parvovirus B19 infection.

Intravenous immunoglobulin in the management of severe early onset red blood cell alloimmunisation

Our objective was to assess the effect of maternal intravenous immunoglobulin (IVIG) administration for severe red blood cell (RBC) alloimmunisation on fetal outcomes. This is a case-control study. Women with a history of severe early onset alloimmunisation resulting in fetal loss in a previous pregnancy and high anti-D or anti-K antibody titres received IVIG in a subsequent pregnancy. We assessed gestational age at first transfusion and fetal outcomes in the subsequent pregnancy and compared these with the outcomes in the previous pregnancy. The most responsible antibody was anti-D in 17 women and anti-K in two others, whilst seven had more than one antibody. In all, 19 women received IVIG in 22 pregnancies, two of which did not even need an intrauterine transfusion (IUT). For previous early losses despite transfusion, IVIG was associated with a relative increase in fetal haemoglobin between treated and untreated pregnancies of 36.5 g/L (95% confidence interval 19.8-53.2, p = 0.0013) and improved perinatal survival (eight of eight vs. none of six, p = 0.001). For previous losses at <20 weeks, it enabled first transfusion deferral in subsequent pregnancies to at least 19.9 weeks (mean 23.2 weeks). Overall, IVIG decreases the severity of haemolytic disease of the fetus and newborn and allows deferral of the first IUT to a safer gestation in severe early-onset RBC alloimmunisation and rarely may even avoid the need for IUT entirely.

Identification and management of fetal anemia due to hemolytic disease

INTRODUCTION

Hemolytic disease of the fetus and newborn (HDFN) is a condition caused by maternal alloantibodies against fetal red blood cells (RBCs) that can cause severe morbidity and mortality in the fetus and newborn. Adequate screening programs allow for timely prevention and intervention resulting in significant reduction of the disease over the last decades. Nevertheless, HDFN still occurs and with current treatment having reached an optimum, focus shifts toward noninvasive therapy options.

AREAS COVERED

This review focusses on the timely identification of high risk cases and antenatal management. Furthermore, we elaborate on future perspectives including improvement of screening, identification of high risk cases and promising treatment options.

EXPERT OPINION

In high-income countries mortality and morbidity rates due to HDFN have drastically been reduced over the last decades, yet worldwide anti-D mediated HDFN still accounts for 160,000 perinatal deaths and 100,000 patients with disabilities every year. Much of these deaths and disabilities could have been avoided with proper identification and prophylaxis. By implementing sustainable prevention, screening, and disease treatment measures in all countries this will systemically reduce unnecessary perinatal deaths. There is a common responsibility to engage in this cause.

Intrauterine transfusion in 103 fetuses with severe anemia caused by parvovirus infection. A multicenter retrospective study

PURPOSE

Evaluating procedure-related complications and perinatal outcomes after intrauterine transfusion (IUT) before or after 20⁺⁰ weeks of gestation in fetuses with severe anemia due to intrauterine human parvovirus B19 infection.

METHODS

A retrospective study investigating fetuses requiring IUT for fetal Parvo B19 infection in two tertiary referral centers between December 2002 and December 2021. Procedure-related complications, intrauterine fetal death (IUFD), and perinatal outcome were correlated to gestational age (GA) at first IUT, the presence of hydrops and fetal blood sampling results.

RESULTS

A total of 186 IUTs were performed in 103 fetuses. The median GA at first IUT was 19⁺³ (13⁺⁰-31⁺⁴) weeks of gestation. IUFD occurred in 16/103 fetuses (15.5%). Overall survival was 84.5% (87/103). Hydrops (p = 0.001), lower mean hemoglobin at first IUT (p = 0.001) and low platelets (p = 0.002) were strongly associated with IUFD. There was no difference observed in fetuses transfused before or after 20⁺⁰ weeks of gestation.

CONCLUSION

IUT is a successful treatment option in fetuses affected by severe anemia due to parvovirus B19 infection in specialized centers. In experienced hands, IUT before 20 weeks is not related to worse perinatal outcome.

Maternal bleeding complications in pregnancies affected by red blood cell alloimmunization

OBJECTIVE

To investigate whether women with red blood cell (RBC)¹ alloimmunization are more likely to experience bleeding complications during pregnancy or delivery than women without RBC alloimmunization.

STUDY DESIGN

Retrospective study involving all singleton pregnancies affected by RBC alloimmunization and without pre-existing maternal bleeding disorders or placenta previa, from 1 July 1999 to 30 June 2019 ("cases"). Only bleedings not related to invasive procedures (amnio- or cordocenteses) were included. Patients who were already at increased risk of pre- or perinatal bleeding due to their medical history (pre-existing bleeding disorders, antithrombotic therapy), or known obstetrics parameters (placental abnormalities etc.) were not included a priori. Cases were compared to controls without RBC alloimmunization, matched for maternal age and body mass index, from the same tertiary referral center in Austria.

RESULTS

130 cases were compared to 130 controls. Cases had significantly more previous pregnancies and miscarriages and their newborns had lower birthweight and were more often transferred to the intensive care unit than newborns of controls. 18/130 (13.8%) cases, compared to 8/130 (6.2%) controls experienced any bleeding during pregnancy or delivery (p = 0.061). Bleeding most often happened during the third trimester (cases: 4.6% vs. controls 0.8%, p = 0.12) and during or after delivery (cases: 7.7% vs. controls: 4.6%, p = 0.168). Binary logistic regression for the prediction of any bleeding complication during pregnancy, delivery or postpartum revealed immunization against RBC antigens as the only independent contributor (p = 0.04). Age, smoking, or previous obstetric history had no influence on the likelihood of maternal bleeding complications. Neither RBC antibody specificity nor titers were predictive of maternal bleeding during pregnancy or delivery.

CONCLUSION

Pregnancies affected by RBC alloimmunization might be at increased risk of maternal bleeding complications during pregnancy and delivery.

A very preterm infant born to mother of mirror syndrome secondary to fetomaternal hemorrhage: a case report

Background

Mirror syndrome (MS) is defined as maternal edema with fetal hydrops and placental edema with different etiologies, such as rhesus isoimmunization and twin-twin transfusion syndrome. Herein, we showcased a unique MS case secondary to fetomaternal hemorrhage (FMH).

Case presentation

A 32-year-old gravida 2 para 0 woman diagnosed with fetal hydrops was admitted to our hospital. Maternal laboratory tests revealed anemia, slightly increased creatinine and uric acid levels, hypoproteinemia, and significantly increased alpha-fetoprotein and hemoglobin-F levels. Therefore, FMH was diagnosed initially. Two days after admission, the woman had unexpectedly progressive anasarca and started to feel chest distress, palpitations, lethargy, and oliguria, and MS was suspected. An emergency cesarean section was performed to terminate the pregnancy. The maternal clinical symptoms and laboratory tests rapidly improved after delivery. A very preterm infant with a 2080-g birthweight at 31 weeks gestation survived after emergency cesarean section, active resuscitation, emergency blood transfusion, abdominocentesis, and advanced life support.

Conclusions

FMH could develop into MS, providing new insights into the etiology of MS. Once MS is diagnosed, emergency cesarean section might be an alternative treatment. The very preterm infant survived with a favorable long-term outcome, and a well-trained perinatal work team is needed for such cases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04179-5.

Neonatal outcomes after percutaneous umbilical cord blood sampling†

Objectives: While percutaneous umbilical cord blood sampling (PUBS) and intrauterine transfusion (IUT) are the standards of care for the management of significant fetal anemia, the neonatal complications resultant from these procedures remain poorly understood. Thus, we aimed to compare neonatal outcomes of the patients undergoing percutaneous umbilical cord blood sampling (PUBS) for intrauterine transfusion (IUT) to gestational age- and sex-matched controls with no indication for and not undergoing PUBS.Methods: This was a retrospective matched cohort study at a single institution from 2000 to 2017. Clinical and demographic data were abstracted from the medical record of patients undergoing PUBS. Neonatal outcomes from pregnancies undergoing PUBS for suspected fetal anemia and from randomly selected gestational age- and sex-matched controls were collected. Neonatal outcomes were compared using matched pairs analysis.Results: There were 64 patients who underwent a total of 178 PUBS with 157 IUT. The most common etiology of fetal anemia was anti-D alloimmunization. On an average, patients undergoing PUBS underwent two procedures (IQR 1,4). There were available neonatal outcomes in 40 patients. The median gestational age at delivery was 34 weeks in both neonates who underwent PUBS and controls. In matched pairs analysis, neonates who underwent PUBS were at higher risk for neonatal complications compared to control neonates (92.5 vs. 55%, OR 4.5, 95% CI 4.5, ∞) . Specifically, neonates who underwent PUBS were more likely to experience respiratory complications compared to controls despite a higher uptake of antenatal corticosteroids.Conclusions: We found that neonates who underwent PUBS experience a higher occurrence of complications which does not appear to be secondary to prematurity alone. Despite higher uptake of antenatal corticosteroids in neonates who underwent PUBS as compared to control neonates, neonates who underwent PUBS had a higher risk of respiratory complications. This study can help to inform patients undergoing PUBS/IUT on the anticipated neonatal outcomes and anticipate needed neonatology resources. While PUBS/IUT is the best treatment known to date for management of fetal anemia, our study highlights the need for further research into the subsequent neonatal complications and how to prevent them.

Identification and management of congenital parvovirus B19 infection

Parvovirus B19 (B19V) infection is well known for its mild, self-limiting clinical presentations in children, such as erythema infectiosum. Approximately 40% of women of childbearing age are susceptible to B19V infection. While maternal B19V infection usually has a good prognosis, B19V can cause severe fetal anaemia and pregnancy loss due to its ability to suppress erythroid progenitor cells. Non-invasive ultrasound monitoring for fetal anaemia is usually performed if maternal seroconversion occurs in the first 20 weeks of gestation, with amniocentesis for fetal infection reserved for those who first present with fetal anaemia or hydrops of unknown cause. Intrauterine transfusion is the standard treatment for severe fetal anaemia and is associated with a significant improvement in survival. However, survivors of hydrops fetalis may have a higher rate of long-term neurodevelopmental complications compared with non-hydropic survivors. This review aims to synthesise published data on the diagnosis, surveillance and outcomes of congenital parvovirus infection to assist clinicians in diagnosing and managing this important condition.

Perinatal outcomes and central nervous system abnormalities following intrauterine fetal transfusion: 17 years' experience in a tertiary center

BACKGROUND

This study aimed to describe the perinatal outcome and central nervous system (CNS) anomalies in fetuses undergoing red blood cell (RBC) intrauterine transfusion (IUT).

METHODS AND MATERIALS

This was an observational single-cohort study carried out at Vall d'Hebron University Hospital in Barcelona, Spain, between 2002 and 2018 in women undergoing RBC IUT for suspected fetal anemia. Primary outcomes were adverse perinatal outcome (intrauterine or neonatal death and termination of pregnancy [TOP]), prenatal or postnatal CNS anomalies, and significant neurological impairment.

RESULTS

A total of 145 RBC transfusions were performed in 68 pregnancies of 60 women. The median gestational age for the first transfusion was 26 weeks (range, 18-32). Twenty-two (32%) fetuses were hydropic at the first transfusion. Fifty-eight pregnancies (85.3%) resulted in live births and 10 (14.7%) in adverse perinatal outcomes. Adverse perinatal outcomes were associated with hydrops (odds ratio [OR], 6.69; 95% confidence interval [CI], 1.53-29.23; P = .012) and gestational age at first transfusion (OR, 0.69; 95% CI, 0.54-0.89; P = .04). Four (5.9%) cases of cerebellar hemorrhage were diagnosed prenatally. In 14 (35%) of the 41 neonates undergoing brain ultrasound and/or magnetic resonance imaging (MRI) abnormalities were reported. The median follow-up was 6.5 years (range, 3 months to 19 years). Significant neurological impairment was reported in two cases (4.2%).

CONCLUSION

In fetuses undergoing intrauterine RBC transfusion, the survival rate is high, particularly in the absence of hydrops and if the gestational age at first transfusion is above 22 weeks. Significant neurological impairment is uncommon, despite the fact that postnatal CNS anomalies at ultrasound or MRI are frequent.

The rhesus incompatible pregnancy and its consequences for affected fetuses and neonates

Rhesus incompatibility in pregnancy may result in haemolytic disease of the fetus and newborn (HDFN). This review discusses the fetal, neonatal and long-term consequences of HDFN and its management. Untreated, the fetal and neonatal prognosis of HDFN is poor. Provision of intravascular intrauterine transfusion (IUT) in a dedicated referral centre significantly reduces perinatal loss. Early-onset, severe fetal anaemia carries a greater risk of adverse fetal and neonatal outcomes and is less amenable to treatment with IUT. Interventions to prevent and treat severe, early onset disease have been investigated, however evidence from randomised controlled trials is required. Neonatal consequences of Rhesus haemolytic disease include early and late postnatal anaemia, and hyperbilirubinaemia leading to bilirubin-induced neurological dysfunction. Neurodevelopmental impairment and adult cardiovascular disease are long-term complications that have been reported in association with severe fetal anaemia. Strategies to prevent fetal hydrops, and further research into the long-term impacts of fetal anaemia may improve health outcomes for adult survivors of HDFN.

Medical therapy to attenuate fetal anaemia in severe maternal red cell alloimmunisation

Haemolytic disease of the fetus and newborn (HDFN) remains an important cause of fetal mortality with potential neonatal and longer-term morbidity. HDFN is caused by maternal red cell alloimmunisation, with IgG antibodies crossing the placenta to destroy fetal erythroid cells expressing the involved antigen. Intrauterine fetal blood transfusion is the therapy of choice for severe fetal anaemia. Despite a strong evidence base and technical advances, invasive fetal therapy carries risk of miscarriage and preterm birth. Procedure-related risks are increased when invasive, in utero transfusion is instituted prior to 22 weeks to treat severe early-onset fetal anaemia. This review focuses upon this cohort of HDFN and discusses intravenous immunoglobin (IVIg) and novel monoclonal antibody (M281, nipocalimab) treatments which, if started at the end of the first trimester, may attenuate the transplacental passage and fetal effects of IgG antibodies. Such therapy has the ability to improve fetal survival in this severe presentation of HDFN when early in utero transfusion may be required and may have wider implications for the perinatal management in general.

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.

A case report of haemolytic disease of the foetus and newborn caused by Alloantibody D and Jka in a Rhesus D negative Nigerian woman: Justification for the implementation of universal access to prophylaxis and evidenced-based best practices

A case report of a 38 years old ABO group A and Rhesus D negative multiparous, gravidae 8 and para 2, Nigerian woman who had a case of premarital miscarriage and who was not offered anti-D prophylaxis as part of her management. Lady went on to develop alloantibody D and Jka. Lady has had 7 further pregnancies post the miscarriage. The first child who is B Rhesus D positive is the only surviving child. The surviving child was delivered severely jaundiced and needed management post-delivery for haemolytic disease of the foetus and newborn (HDFN). Lady has had a history of a stillbirth. She was given a non-clinically indicated anti-D prophylaxis during the second pregnancy despite having been previously sensitized. The second baby died 3 months after delivery from complications of HDFN. She had had a further history of 5 miscarriages. She has had challenge with conception since 2010. Alloantibody testing confirms the presence alloantibody D and anti-Jka. Finding from this is a clear case of sub-optimal laboratory, obstetric and neonatal care offered particularly to pregnant women who are Rh D negative and those with alloantibodies in Nigeria. The Nigerian government will need to implement evidenced-based best practices; determination of alloantibody status of pregnant women during their first antenatal visit; provision of facilities for alloantibody identification, titration, quantification and feto maternal haemorrhage testing (FMH); implementation of a policy on universal access to anti-D prophylaxis for pregnant Rh D negative women who are not previously sensitized; provision of facilities required for the optimal intrauterine management of HDFN (foetal genotype testing, intrauterine transfusion, doppler ultrasound to diagnose anaemia inutero and provision of donor blood that meet the minimum requirements for intrauterine transfusion); determination of Rh D status of women who require a termination of pregnancy and provision of prophylactic anti-D for those found Rh D negative within 72 hours of procedure and the optimization of the knowledge of Medical Laboratory Scientist, Obstetricians, Neonatologist, Pharmacist and Traditional Birth Attendants in a bid to reduce the residual number of women who become sensitized and the number of preventable deaths of babies with HDFN.

Intraperitoneal transfusion for severe, early-onset rhesus disease requiring treatment before 20 weeks of gestation: A consecutive case series

OBJECTIVE

To describe the management and perinatal outcomes of pregnancies affected by severe, early onset Rhesus isoimmunization treated with fetal intraperitoneal transfusions (IPTs).

STUDY DESIGN

A ten-year consecutive case series of fetuses undergoing IPTs before 20 weeks gestation at Wessex Fetal Medicine Unit, Southampton, UK. Women with fetuses at risk of early onset fetal anaemia (before 20 weeks gestation) were identified from their obstetric history and maternal antibody levels at the time of booking. They were referred to our tertiary referral center. The decision to initiate transfusion was aided by middle cerebral artery peak systolic velocity as an indicator of fetal anaemia. No fetus was hydropic at the first transfusion. IPTs were commenced from as early as 15 weeks gestation in fetuses with difficult vascular access and performed regularly using this method until the cord could be successfully entered for intravascular transfusions. The main outcome measures were procedure and non procedure-related perinatal losses.

RESULTS

11 fetuses underwent 45 IPTs. 10/11 (91%) were delivered after 33 weeks gestation. There was one perinatal loss 1/11 (9%: 95% C.I 1.6-38%) from a cord accident during intravascular transfusion at 26 weeks gestation. There were no procedure related fetal losses or complications at the time of early IPTs.

CONCLUSIONS

Previous studies report a perinatal loss rate with early intrauterine transfusion of 24% in gestations below 20 weeks using the intravascular route. This series suggests that intraperitoneal transfusion can be a safe and effective treatment for severe fetal anaemia at early gestations where vascular access is difficult.

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.

M281, an anti-FcRn antibody, inhibits IgG transfer in a human ex vivo placental perfusion model

BACKGROUND

The transfer of pathogenic immunoglobulin G antibodies from mother to fetus is a critical step in the pathophysiology of alloimmune and autoimmune diseases of the fetus and neonate. Immunoglobulin G transfer across the human placenta to the fetus is mediated by the neonatal Fc receptor, and blockade of the neonatal Fc receptor may provide a therapeutic strategy to prevent or minimize pathological events associated with immune-mediated diseases of pregnancy. M281 is a fully human, aglycosylated monoclonal immunoglobulin G1 antineonatal Fc receptor antibody that has been shown to block the neonatal Fc receptor with high affinity in nonclinical studies and in a phase 1 study in healthy volunteers.

OBJECTIVE

The objective of the study was to determine the transplacental transfer of M281 and its potential to inhibit transfer of immunoglobulin G from maternal to fetal circulation.

STUDY DESIGN

To determine the concentration of M281 required for rapid cellular uptake and complete saturation of the neonatal Fc receptor in placental trophoblasts, primary human villous trophoblasts were incubated with various concentrations of M281 in a receptor occupancy assay. The placental transfer of M281, immunoglobulin G, and immunoglobulin G in the presence of M281 was studied using the dually perfused human placental lobule model. Immunoglobulin G transfer was established using a representative immunoglobulin G molecule, adalimumab, a human immunoglobulin G1 monoclonal antibody, at a concentration of 270 μg/mL. Inhibition of immunoglobulin G transfer by M281 was determined by cotransfusing 270 μg/mL of adalimumab with 10 μg/mL or 300 μg/mL of M281. Concentrations of adalimumab and M281 in sample aliquots from maternal and fetal circuits were analyzed using a sandwich enzyme-linked immunosorbent assay and Meso Scale Discovery assay, respectively.

RESULTS

In primary human villous trophoblasts, the saturation of the neonatal Fc receptor by M281 was observed within 30-60 minutes at 0.15-5.0 μg/mL, suggesting rapid blockade of neonatal Fc receptor in placental cells. The transfer rate of adalimumab (0.23% ± 0.21%) across dually perfused human placental lobule was significantly decreased by 10 μg/mL and 300 μg/mL of M281 to 0.07 ± 0.01% and 0.06 ± 0.01%, respectively. Furthermore, the transfer rate of M281 was 0.002% ± 0.02%, approximately 100-fold lower than that of adalimumab.

CONCLUSION

The significant inhibition of immunoglobulin G transfer across the human placental lobule by M281 and the minimal transfer of M281 supports the development of M281 as a novel agent for the treatment of fetal and neonatal diseases caused by transplacental transfer of alloimmune and autoimmune pathogenic immunoglobulin G antibodies.

Management of red blood cell alloimmunization in pregnancy

The main cause of fetal anemia is maternal red blood cell alloimmunization (AI). The search of maternal antibodies by indirect antiglobulin test allows screening for AI during pregnancy. In case of AI, fetal genotyping (for Rh-D, Rh-c, Rh-E and Kell), quantification (for anti-rhesus antibodies) and antibody titration, as well as ultrasound monitoring, are performed. This surveillance aims at screening for severe anemia before hydrops fetalis occurs. Management of severe anemia is based on intrauterine transfusion (IUT) or labor induction depending on gestational age. After intrauterine transfusion, follow-up will focus on detecting recurrence of anemia and detecting fetal brain injury. With IUT, survival of fetuses with alloimmunization is greater than 90% but 4.8% of children with at least one IUT have neurodevelopmental impairment.

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.

Complications of intrauterine intravascular blood transfusion: lessons learned after 1678 procedures

OBJECTIVE

Maternal alloimmunization to fetal red-blood-cell antigens is a major cause of fetal anemia, which can lead to hydrops and perinatal death if untreated. The cornerstone of management during pregnancy is intrauterine intravascular blood transfusion (IUT). Although this procedure is considered relatively safe, complications continue to occur. The aim of this study was to evaluate rates of procedure-related complications and perinatal loss following IUT, and their change over time, in order to identify factors leading to improved outcome.

METHODS

This was a retrospective analysis of all IUTs for red-cell alloimmunization performed at the national referral center for fetal therapy in The Netherlands, from 1988 to 2015. Differences in complication rates and their associations with alterations in transfusion technique after 2001 were assessed.

RESULTS

Between 1988 and 2015, 1678 IUTs were performed in 589 fetuses. For IUTs performed in 2001 and onwards, there was significant improvement in survival (88.6% vs 97.0%, P < 0.001) and a decline in procedure-related complications per fetus (9.8% vs 3.3%, P = 0.001) and per procedure (3.4% vs 1.2%, P = 0.003) compared with those performed before 2001. Procedure-related perinatal loss declined from 4.7% to 1.8% per fetus (P = 0.053). Beneficial changes in transfusion technique were routine use of fetal paralysis, increased use of intrahepatic transfusion and avoidance of arterial puncture.

CONCLUSIONS

IUT has become an increasingly safe procedure in recent years when performed by experienced hands. The chosen technique should be fine-tuned according to the patient's individual situation. The declining complication rates are most likely related to center volume: this rare procedure is best performed in experienced fetal therapy centers. © 2016 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Ethical issues in fetal therapy

The introduction of routine fetal ultrasound and the technical improvements in ultrasound equipment have greatly increased our ability to diagnose fetal anomalies. As a consequence, congenital anomalies are diagnosed today earlier and in a greater number of patients than ever before. The development of fetal intervention and fetal surgery techniques, improved anesthesia methodology, and sophisticated perinatal care at the limits of viability, have now made prenatal management of some birth defects or fetal malformations a reality. The increasing number of indications for fetal therapy and the apparent desire of parents to seek out these procedures have raised concern regarding the ethical issues related to the therapy. While fetal therapy may have a huge impact on the prenatal management of some congenital birth defects and/or fetal malformations, because of the invasive nature of these procedures, the lack of sufficient data regarding long-term outcomes, and the medical/ethical uncertainties associated with some of these interventions there is cause for concern. This chapter aims to highlight some of the most important ethical considerations pertaining to fetal therapy, and to provide a conceptual ethical framework for a decision-making process to help in the choice of management options.

Health-Related Quality of Life and Behavioral Functioning after Intrauterine Transfusion for Alloimmune Anemia

OBJECTIVE

To assess health-related quality of life (HRQOL) and behavioral functioning in children and adolescents treated before birth with intrauterine intravascular blood transfusion for alloimmune anemia.

STUDY DESIGN

Cross-sectional cohort study conducted at the Dutch referral center for the management of fetal alloimmune anemia. Follow-up data were available for 285 children at a mean age of 10.5 years (range, 3-21.5 years) with a response rate for questionnaires of 97%. Child-, adolescent-, and parent-rated HRQOL was evaluated with The Netherlands Organization for Applied Scientific Research Child/Adult Quality of Life Questionnaire (TACQOL/TAAQOL). Parents reported on behavioral functioning with the Strengths and Difficulties Questionnaire. Scores were compared with Dutch norm data.

RESULTS

Significantly lower scores were reported by parents of children 6-11 years of age compared with Dutch norms on 3 scales: cognitive functioning, social functioning, and positive emotions (P < .00, P = .02, and P = .04). In children aged 8-11 years only the cognitive functioning scale score was significantly lower compared with Dutch norms (P = .01). The children aged 12-15 years reported higher scores on the negative emotions scale (P = .02). When corrected for multiple testing, only the parent-rated cognitive functioning scale remained significant (P < .001). Regarding the HRQOL scores of adolescents aged ≥16 years, no differences were detected. Overall, behavioral difficulties were reported in 37/246 (15%) children aged 3-16 years, and were associated with maternal educational levels (P < .001).

CONCLUSION

Parents reported lower scores on cognitive functioning in their children aged 6-11 years compared with norms. Behavioral difficulties were more prevalent than norms, and were associated with maternal educational level. Outcomes of children after intrauterine intravascular blood transfusion were quite good overall.

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

OBJECTIVES

To study the perinatal survival and procedure-related (PR)complications after intrauterine transfusions in red cell alloimmunization.

METHODS

Prospective data of 102 women with Rh-alloimmunized pregnancy undergoing intrauterine intravascular transfusion for fetal anemia, from January 2011 to October 2014 were analyzed. Main outcome measures were perinatal survival and procedure-related (PR) complications.

RESULTS

A total of 303 intrauterine transfusions were performed in 102 women. Of 102 fetuses, 22 were hydropic at first transfusion. The mean period of gestation and hematocrit at first transfusion was 26.9 ± 3.3 weeks (range 19.7-33.8 weeks) and 17 ± 7.82 % (range 5.7-30 %), respectively. Average number of transfusions was 2.97 (range 1-7) per patient. Overall survival was 93 % and mean period of gestation at delivery was 34.5 ± 1.94 (range 28.3-37.4) weeks. Mean hematocrit at delivery was 36.9 ± 8.77 % (range 10-66 %). Fetal death occurred in four cases (3PR), neonatal death occurred in three cases (2PR). Emergency cesarean delivery after transfusion was performed in four pregnancies. The total PR complication rate was 2.97 %, resulting in overall PR loss in 1.65 % per procedure.

CONCLUSION

Our results compare favorably with other studies published in the literature. Intravascular transfusion is a safe procedure improving perinatal survival in fetuses with anemia due to Rh-alloimmunization.

Changes in fetal myocardial performance index following intravascular transfusion: preliminary report

OBJECTIVE

To investigate the changes in fetal left ventricle myocardial performance index (MPI) following intrauterine intravascular transfusion (IUT).

METHODS

Prospective study, including 25 IUT performed in 13 singleton pregnancies with maternal Rh D alloimmune disease. Left ventricle MPI was evaluated prior to transfusion and repeated 24 h after each procedure. Delta MPI was calculated as the difference between post- and pre-transfusion MPI z-scores. Multilevel regression analysis was used to examine the association between delta MPI and gestational age at procedure, fetal middle cerebral artery peak velocity MoM, pre- and post-MPI and hemoglobin z-score values, the volume of blood transfused and feto-placental volume percentage expansion. Adjustments were made for repeated measurements within the same fetus, and across different time points. The significance level was set as 0.05.

RESULTS

MPI z-score values increased significantly following transfusion (delta MPI = 1.10 ± 2.47, p=0.036). Delta MPI showed a significant correlation with gestational age at transfusion (r= -0.47, p=0.018), pre-transfusion MPI z-score (r= -0.50, p=0.012) and feto-placental volume percentage expansion (r= -0.41, p=0.044).

CONCLUSION

Left ventricle MPI increases significantly after intrauterine blood transfusion and greater changes are associated with procedures at an earlier gestational age, lower pre-transfusion MPI z-scores and smaller feto-placental volume expansion.

Fetal Intracardiac Transfusions in Hydropic Fetuses with Severe Anemia

Introduction: Fetal anemia can have significant perinatal morbidity and mortality, particularly with onset prior to 20 weeks of gestation. Materials and Methods: We detail a case-cohort study (n = 8) of all women who underwent fetal in-utero, intracardiac transfusion prior to 24 weeks of gestation (7 women before 20 + 1 weeks), between March 2004 and September 2014, in a supraregional Fetal Medicine Center in the United Kingdom, comprising 2.2% of all transfusions performed during this period. All the fetuses were hydropic, with high maternal BMI, and had severe anemia as an indicator for transfusion. It was an attempt to perform intravascular transfusion when other common routes of fetal vascular access had failed. Results: There were 2 intrauterine deaths (25%), both of which were associated with in-utero transfusion and fulminant parvovirus B19 infection. The perinatal survival rate was 75% (6/8). Discussion: Fetal in-utero, intravascular transfusion by the intracardiac route may be used to correct severe early-onset anemia. It is particularly useful when technical issues of fetal size, early gestation (<20 weeks), maternal adiposity, and hydrops fetalis make umbilical cord or intrahepatic vein puncture technically difficult. Survival rates appear comparable to other series of pregnancies where in-utero transfusion is performed at early gestation.

Reassessing critical maternal antibody threshold in RhD alloimmunization: a 16-year retrospective cohort study

OBJECTIVE

To determine the critical maternal antibody threshold for specialist referral in cases of RhD alloimmunization.

METHODS

This was a retrospective cohort study, covering a 16-year period at the national tertiary fetal medicine center for management of alloimmunization. Data concerning RhD alloimmunized pregnant women were extracted from an institutional database and maternal anti-D antibody levels were cross-checked with the national reference laboratory. Fetal hemoglobin (Hb) levels were determined only at the first intrauterine transfusion (IUT) and were compared with the pretransfusion maternal anti-D antibody level (IU/mL). Sensitivity, specificity and positive and negative predictive values of maternal antibody thresholds for detecting moderate to severe (Hb ≤ 0.64MoM) fetal anemia were calculated.

RESULTS

Between 1996 and 2011, 66 women underwent a first IUT for RhD alloimmunization at our institution. The highest serum anti-D antibody level was extracted for 208 RhD alloimmunized women who did not require IUT during the last 10 years of the study period. The traditional maternal antibody threshold of > 15 IU/mL failed to detect 20% of cases of moderate to severe fetal anemia. The ≥ 4 IU/mL threshold had 100% sensitivity but a 45% false-positive rate. The optimal anti-D antibody threshold for specialist referral in our population was ≥ 6 IU/mL; at this level, no case of moderate to severe anemia was missed and specificity was 61%. Use of this threshold would have eliminated 10% of referrals to our fetal medicine unit without compromising fetal outcomes.

CONCLUSIONS

Setting the critical maternal RhD antibody level at >15 IU/mL does not provide sufficient sensitivity. The lower threshold of ≥ 4 IU/mL, though sensitive, is associated with a 45% false-positive rate. In our population, a threshold of ≥ 6 IU/mL minimizes false-positive referrals while maintaining 100% sensitivity for moderate to severe fetal anemia.

Intrauterine blood transfusion: current indications and associated risks

Fetal anemia is a serious complication in pregnancy and associated with perinatal mortality and morbidity. During 25 years of worldwide experience with intravascular intrauterine blood transfusion, a variety of indications have been described. Intrauterine transfusion (IUT) treatment is considered most successful for fetal anemia due to red cell alloimmunization. Moreover, the use of this procedure has also been reported in pregnancies with parvovirus B19 infection, fetomaternal hemorrhage and placental chorioangiomas, for example. This review focuses on the current indications of intrauterine blood transfusions. In addition, we describe the potential complications of IUT treatment.