Fetomaternal hemorrhage (FMH), an update: review of literature and an illustrative case

Massive fetomaternal hemorrhage in a monochorionic-diamniotic twin pregnancy: a case report

Fetomaternal hemorrhage (FMH) result into severe, life-threatening fetal anemia and cause intrauterine death of the fetus. It is tough for an early diagnosis of FMH before pregnancy and few authors reported FMH in a twin pregnancy. Therefore, we reported a case of massive FMH. The patient felt a decrease in fetal movements at 33⁺⁵ gestational weeks. Cardiotocography showed sinusoidal heart rate patterns in one fetus. The fetal hemoglobin level in maternal blood was 6.4% (normal range for single pregnancy, 0.0%-2.0%). Since the patient was diagnosed with fetal distress, cesarean section was performed and both babies delivered to receive neonatal treatment. Severe anemia was apparent in both neonates, based on red blood cell count, hemoglobin concentration, and hematocrit of 0.75 × 10¹²/L and 0.61 × 10¹²/L, 2.8 g/dL and 2.4 g/dL, and 10.0% and 8.4%, respectively. The neonates were admitted to the intensive care unit for prematurity care and presently are well. In our experience, an early diagnosis of FMH contributed to saving fetus. Obstetricians should highlight fetal movements counting to every patient. Once massive FMH occurs in monochorionic twins, both fetuses may develop severe anemia and require emergency intervention.

Massive fetomaternal hemorrhage: a case series and review of literature

Objectives

Massive fetomaternal hemorrhage (FMH) is a rare and difficult to diagnose event that can have catastrophic outcomes. Although many etiologies have been associated with FMH, the majority of cases are idiopathic and affect uncomplicated pregnancies. The prevailing symptom is decreased fetal movements but some cases are asymptomatic. Changes in the fetal Doppler ultrasound, a sinusoidal cardiotocographic pattern, neonatal anemia, unexplained hydrops or stillbirth can raise suspicion that such an event has occurred.

Case presentation

This article presents a case series of severe FMH diagnosed in our center between 2011 and 2020 as well as a review of the current available literature.

Conclusions

We highlight the importance of the clinician’s awareness on detecting this rare but potentially life-threatening event.

Diagnostic accuracy of Kleihauer-Betke (Kb) testing to predict fetal outcomes associated with fetomaternal hemorrhage: a retrospective cohort study

OBJECTIVE

To evaluate the diagnostic and screening utility of Kleihauer-Betke (KB) testing as a triage tool in predicting adverse fetal outcomes associated with fetomaternal hemorrhage (FMH).

STUDY DESIGN

Single center retrospective cohort study evaluated a primary composite outcome of fetal complications associated with FMH between KB-negative and KB-positive test groups. Screening tests for sensitivity, specificity, positive predictive value and negative predictive value were determined.

RESULTS

641 women (97%) had KB-negative and 22 (3%) had KB-positive tests. The primary composite outcome between KB-negative and KB-positive pregnancies was similar (30% vs. 36%, p = 0.54). Screening exhibited high specificity (97%), however, test sensitivity was poor (4%) with only moderate positive and negative predictive values (36.4 and 69.7%).

CONCLUSION

Fetal outcomes associated with FMH were not significantly different between KB-positive and KB-negative test cohorts; KB testing offers no diagnostic precision in the emergency triage evaluation of women with suspected FMH.

Reduced fetal movements: the case of Fetomaternal Hemorrhage. Case series and proposal of a management protocol

Fetomaternal hemorrhage (FMH) was reported more than 60 years ago for the first time defined by the transfer or transfusion of fetal blood into the maternal circulation before or during delivery. The transfused volume is usually very small but when this value exceeds, it may be clinically significant. Antenatal diagnosis of severe FMH is difficult and it can be suspected in case of reduction of fetal movements, abnormal cardiotocography and ultrasound. FMH is associated to different adverse outcomes and admission to neonatal intensive care. The low incidence of FMH limits the studies, thus being able to rely only on diagnosis and retrospective studies. We present case series of FMH and analyze the steps with the purpose of defining a flow-chart for early diagnosis and management of FMH.

Severe Neonatal Anemia Due to Spontaneous Massive Fetomaternal Hemorrhage at Term: An Illustrative Case with Suspected Antenatal Diagnosis and Brief Review of Current Knowledge

Fetomaternal hemorrhage is defined as transfer of fetal blood into placental circulation and therefore into maternal circulation during pregnancy, and represents an important contributor to intrauterine fetal demise and neonatal death. The condition is rarely diagnosed prenatally because clinical findings are often nonspecific, and it is unpredictable. In this paper we present an illustrative case of massive spontaneous fetomaternal hemorrhage where the diagnosis was highly suspected antenatally based on maternal reported reduced fetal movements, abnormal suggestive cardiotocographic trace, and increased peak systolic velocity in the fetal middle cerebral artery. We discuss obstetrical and neonatal management and review the current knowledge in the literature. Maintaining a high index of suspicion for this condition allows the obstetrician to plan for adequate diagnostic tests, arrange intrauterine treatment or delivery, and prepare the neonatal team.

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.

Fetomaternal hemorrhage occurred in one fetus of dichorionic twin pregnancy

In a twin pregnancy, it may be difficult to notice the decreased fetal movements, which is one of the main symptoms of fetomaternal hemorrhage, in one fetus due to the movements of the other fetus.

Severe neonatal anemia affected by massive fetomaternal hemorrhage: a single-center retrospective observational study

OBJECTIVES

Massive fetomaternal hemorrhage (FMH) is a rare but sometimes life-threatening event, and surviving neonates may suffer major neurological complications. Severe neonatal anemia (SNA) affected by massive FMH is less reported in the literature. This study aims to explore the clinical characteristics, laboratory diagnoses, treatments and outcomes of SNA affected by massive FMH.

METHODS

Data were collected retrospectively from the hospital's electronic medical record system. All neonates born in the hospital and admitted to the neonatal unit diagnosed as SNA affected by massive FMH from 1 January 2013 to 31 June 2017 were included.

RESULTS

A total of 8 cases of SNA affected by FMH were identified among 6825 neonates admitted to the neonatal unit. They all presented with pallor but without hydrops at birth. Median gestational age and birthweight were 37^5/7 (36^0/7‒40^1/7) weeks and 2,625 (2300‒3050) g, respectively. Median hemoglobin level was 39.5 (25‒53) g/L at birth and 109.5 (94-127) g/L at discharge. Median maternal serum alpha-fetoprotein (AFP) was 3958.5 (1606‒14,330) ng/mL, which was significantly increased. Three out of eight cases manifested as antenatal decreased fetal movement. Only 1 with the lowest initial hemoglobin 25 g/L manifested as characteristic sinusoidal fetal heart rate tracing and suffered severe neonatal asphyxia and hypovolemic shock. Having experienced resuscitation, he was admitted to the neonatal unit and received twice transfusion of cross-matched red blood cells there. Another case with the initial hemoglobin 45 g/L received positive pressure ventilation and once transfusion. All cases were successfully discharged with a median hospital stay of 8 (5-12) days. Follow-up was available for 6 (75%) of 8 neonates (age range 13 months to 50 months), and all infants were observed to be in good condition with normal neurological status. In our series of eight cases, there were no neonatal deaths.

CONCLUSION

This study strengthens the idea that maternal AFP testing is valuable to confirm massive fetomaternal hemorrhage. Surviving neonates of massive FMH might have a good outcome despite severe anemia at birth.

Evaluation of machine learning-driven automated Kleihauer-Betke counting: A method comparison study

INTRODUCTION

The Kleihauer-Betke (KB) test is the diagnostic standard for the quantification of fetomaternal hemorrhage (FMH). Manual analysis of KB slides suffers from inter-observer and inter-laboratory variability and low efficiency. Flow cytometry provides accurate quantification of FMH with high efficiency but is not available in all hospitals or at all times. We have developed an automated KB counting system that uses machine learning to identify and distinguish fetal and maternal red blood cells (RBCs). In this study, we aimed to evaluate and compare the accuracy, precision, and efficiency of the automated KB counting system with manual KB counting and flow cytometry.

METHODS

The ratio of fetal RBCs of the same blood sample was quantified by manual KB counting, automated KB counting, and flow cytometry, respectively. Forty patients were enrolled in this comparison study.

RESULTS

Comparing the automated KB counting system with flow cytometry, the mean bias in measuring the ratio of fetal RBCs was 0.0048%, with limits of agreement ranging from -0.22% to 0.23%. Using flow cytometry results as a benchmark, results of automated KB counting were more accurate than those from manual counting, with a lower mean bias and narrower limits of agreement. The precision of automated KB counting was higher than that of manual KB counting (intraclass correlation coefficient 0.996 vs 0.79). The efficiency of automated KB counting was 200 times that of manual counting by the certified technologists.

CONCLUSION

Automated KB counting provides accurate and precise FMH quantification results with high efficiency.

Case Report of Anemia Following Fetal-Maternal Hemorrhage

BACKGROUND

Any maternal history of blood loss, ABO or Rh incompatibility, and hydrops fetalis often leads to suspicion of neonatal anemia postnatally. When maternal history consists only of decreased fetal movement, recognition of neonatal anemia can be problematic.

CLINICAL FINDINGS

This case was a transported late preterm neonate who presented initially with persistent hypoxia unresponsive to usual respiratory support. On examination, mild paleness was noted.

PRIMARY DIAGNOSIS

Anemia caused by fetal-maternal hemorrhage was the ultimate diagnosis confirmed by a Kleihauer-Betke test on maternal serum examining fetal cells.

INTERVENTIONS

Neonatal resuscitation included positive pressure ventilation, oxygen, and intubation. However, oxygenation did not improve prompting consultation with the neonatologist. Sedation and a paralytic were given. A chest radiograph ruled out pneumothoraces and pleural effusions as causative. Initiation of inhaled nitric oxide produced a mild response. Eventually, the transport nurse obtained a complete blood count indicating severe anemia, which prompted an emergent blood transfusion. The accepting neonatology team consulted with the obstetrician and a Kleihauer-Betke test was performed on mother's blood confirming a large fetal-maternal hemorrhage.

OUTCOMES

This neonate responded well to blood transfusions, a pressor, and respiratory support and was discharged home at 7 days of life.

PRACTICE RECOMMENDATIONS

Recognition of postnatal anemia is vital to sustaining life and this can occur in the transport environment. When maternal history is nonspecific and a neonate is hypoxic, uncommon causes of hypoxia can be identified with consultation and a complete blood count.

Placental Histology After Minor Trauma in Pregnancy: A Pilot Study

OBJECTIVE

Trauma in pregnancy may cause placental abruption. Consequences of moderate placental injury on neurodevelopment are unknown. The aim was to evaluate placental histology after maternal trauma.

METHODS

A prospective study was conducted at 2 tertiary medical centers in the Netherlands. Placentas from women exposed to maternal trauma ≥ 20 weeks' gestational age were histologically examined. Neurological follow-up of the infants was performed at 1 year of age by means of Alberta Infant Motor Scale. Histological findings were compared to placentas from pregnancies without trauma.

PRINCIPAL RESULTS

Thirteen placentas were investigated in the trauma group. The control group consisted of 15 placentas. Placental pathology was seen more often in the trauma cases (11 of the 13) than in the controls (6 of the 15), P = .024. Neurological follow-up was normal.

CONCLUSIONS

In this small population, majority of the placentas showed pathology after minor trauma in pregnancy without consequences for neurodevelopment at 1 year.

Cardiotocography findings of early-stage chronic fetomaternal hemorrhage after the presentation of reduced fetal movement

In the current case of fetomaternal hemorrhage with reduced fetal movements, the findings of cardiotocography (CTG) seemed to be indicating reassuring fetal status; however, a late deceleration and sinusoidal heart rate (SHR)-like findings were observed following a weak uterine contraction. Altogether, this case indicates that the presence of reduced fetal movements may precede the appearance of SHR patterns on CTG in cases of chronic fetomaternal hemorrhage.

Untimely diagnosis of fetomaternal hemorrhage: what went wrong?

Fetomaternal hemorrhage (FMH) is an obstetrical challenge. It is defined as a passage of fetal blood into the maternal circulation or vice versa, which might complicate pregnancy or delivery. Most cases of acute and chronic FMH are idiopathic in origin and involve uncomplicated near-term pregnancies. Yet, due to the lack of universal screening, heterogeneous clinical presentation and insufficient clinicians awareness, in some cases FMH may present as immediate fetal compromise or even stillbirth as the most devastating consequence. We made a review of the literature of the FMH clinical cases of fetal/neonatal death in order to focus on the available diagnostic tools and their limitations. Cardiotocography, biophysical profile, middle cerebral artery peak systolic volume and current laboratory tests were studied and evaluated as diagnostic tools for FMH. International guidelines are needed to help clinicians make a prompt identification of FMH. Moreover, a standardized management protocol is essential in order to improve fetal-neonatal outcomes.

Persistent pulmonary hypertension of the newborn after fetomaternal hemorrhage

BACKGROUND

Newborns with anemia are at increased risk of persistent pulmonary hypertension of the newborn (PPHN), yet reports on the association between fetomaternal hemorrhage (FMH) and PPHN are rare. To optimize care for pregnancies complicated by FMH, clinicians should be aware of the risks of FMH and the possible diagnostic and therapeutic options. To increase the current knowledge, the incidence of PPHN and short-term neurologic injury in FMH cases were studied.

STUDY DESIGN AND METHODS

We included all FMH cases (≥30 mL fetal blood transfused into the maternal circulation) admitted to our neonatal unit between 2006 and 2018. First, we evaluated the incidence of PPHN and short-term neurologic injury. Second, we studied the potential effect of intrauterine transfusion (IUT).

RESULTS

PPHN occurred in 37.9% of newborns (11 of 29), respectively, 14.3% (one of seven) and 45.5% (10 of 22) in the IUT group and no-IUT group (p = 0.20). The mortality rate was 13.8% (4 of 29). Severe brain injury occurred in 34.5% (10 of 29), respectively, and 14.3% (one of seven) and 40.9% (nine of 22) in the IUT group and no-IUT group (p = 0.37).

CONCLUSION

Awareness should be raised among perinatologists and neonatologists about the possible life-threatening consequences of FMH, as more than one-third of neonates with anemia due to FMH experience PPHN and suffer from severe brain injury. Antenatal treatment with IUT seems to reduce these risks. Specialists should therefore always consider fetal anemia in FMH cases and refer patients to a fetal therapy center. If anemia is present at birth, it should be corrected promptly and neonatologists should be aware of signs of PPHN.

The Recurrence Risk of Fetomaternal Hemorrhage

Massive fetomaternal hemorrhage (FMH) can cause devastating pregnancy outcomes. Perinatal prognosis may be improved by intrauterine transfusion, but the appropriate management for these pregnancies remains unclear. To determine the recurrence risk of FMH after intrauterine transfusion, we performed a systematic review of all case reports/series of patients with proven FMH treated with intrauterine transfusion and who had subsequent follow-up of at least 72 h until delivery. This revealed 13 cases, with 1 additional case from our institution. Ten patients (71.4%) had a second episode of FMH requiring a second intrauterine transfusion. Five patients (35.7%) required at least 3 intrauterine transfusions. The time interval between intrauterine transfusions was progressively reduced. The gestational age at the onset of signs/symptoms was 26.6 ± 2.1 weeks, and gestational age at delivery was 34.2 ± 4.2 weeks. Two cases of fetal demise (14.3%) and no neonatal deaths were recorded. Limited postnatal follow-up on 8 neonates was normal. The mean neonatal hemoglobin and transfusion rates were 13.2 ± 5.7 g/dL and 33.3%, respectively. Close fetal monitoring, likely daily, is necessary to recognize FMH recurrence. Several transfusions may be necessary once FMH is diagnosed if pregnancy is allowed to continue > 72 h.