Fetomaternal hemorrhage: Evidence from a multihospital healthcare system that up to 40% of severe cases are missed

Routine maternal ABO/Rhesus D blood typing can alert of massive foetomaternal haemorrhage

BACKGROUND AND OBJECTIVES

Spontaneous massive foetomaternal haemorrhage (SM-FMH) is a rare yet critical condition that poses substantial risk to foetal health and survival. Existing data indicate that many cases may be undiagnosed. The current study aimed to investigate and validate the utility of identifying mixed field red blood cell (RBC) agglutination during maternal blood typing as a diagnostic aid for SM-FMH.

MATERIALS AND METHODS

Retrospective analysis of medical records from neonates born at our tertiary, university-affiliated medical centre between 2016 and 2023 was performed. Diagnosis of SM-FMH was based on neonates born with severe anaemia (haematocrit [HCT] <15%) within the first 24 h post-delivery with positive maternal Kleihauer-Betke (KB) test. Maternal ABO/Rhesus D (RhD) blood typing results were scrutinized with the primary objective of assessing the ability to identify dual RBC populations in cases clinically diagnosed with SM-FMH.

RESULTS

Among 29,192 neonates studied, a mere 0.02% (5 cases) exhibited severe SM-FMH. Notably, a mixed field RBC agglutination was discerned in 80% (4/5) of these cases.

CONCLUSION

This study underscores the significance of detecting mixed field RBC agglutination during antepartum maternal ABO/RhD blood typing as a potential indicator for SM-FMH. Increased awareness among blood bank technology specialists and obstetricians regarding these laboratory findings could prove instrumental in saving foetal lives.

Spontaneous massive fetomaternal hemorrhage: two case reports and a literature review of placental pathology

BACKGROUND

Massive fetomaternal hemorrhage (FMH) is a rare event during pregnancy that may cause severe fetal anemia or death.

CASE PRESENTATION

This paper reports two cases of fetomaternal hemorrhage with unexplained reasons. Both cases required emergency caesarean sections for non-reassuring fetal status and were treated with neonatal blood transfusion. Fetomaternal hemorrhage was confirmed via maternal Kleihauer-Betke test.

CONCLUSION

We found parenchymal pallor, increased nucleated red blood cells (nRBCs), and syncytial knots (SKs) in the placentas, which are compatible with fetal anemia. Immunohistochemical staining indicated VEGF, CD34, and CD31 expression in the endothelial cells of the capillaries, characteristic of massive FMH placenta. This article also reviews the particular histopathological changes in FHM placenta according to the placental lesion classification system.

Prenatal diagnosis of fetomaternal hemorrhage by a novel hydrogel fluoroimmunoassay that accurately quantifies fetal haemoglobin

Objective: Fetomaternal hemorrhage (FMH) is an alloimmunization resulting caused by the incompatibility between fetal and maternal blood. For the prevention of newborn haemolytic disease (HDN), it is crucial to quantify the amount of fetomaternal hemorrhage. However, the classical Kleihauer-Betke test (K-B test) for detecting fetomaternal hemorrhage is limited by experimental tools and conditions and is not suitable for routine clinical use. Consequently, the method of prenatal diagnosis of fetomaternal hemorrhage applicable to the clinic is a topic worthy of further study. Therefore, it is worthwhile to further investigation on the clinically applicable prenatal diagnosis method for fetomaternal hemorrhage. Methods: This experiment demonstrates hydrogel's ability to separate sensitized red blood cells from soluble antibodies. Using flow cytometry the fluorescence values of sensitized red blood cells and fluorophore-labeled antibodies were measured, and the testing steps for the detection products of a novel technology were determined. The properties of a hydrogel fluoroimmunoassay were evaluated by distinguishing between the amounts of fetal and adult haemoglobin. The precision of this technology is evaluated using the Kleihauer-Betke test as a comparison. Results: This experiment compared the detection of haemoglobin fluorescence in adults (n = 2) and fetuses (n = 6). At the same time, the fluorescence intensity of different fetal haemoglobin (HbF) in adult haemoglobin (HbA) was calculated. The fluorescence value is 1.6% when the fetal hemoglobin concentration is 0.1%. Conclusion: The novel hydrogel fluoroimmunoassay can accurately determine the fluorescence intensity by flow cytometry to differentiate fetal haemoglobin from adult haemoglobin, quantitatively prenatally diagnose fetal haemoglobin, address the incompatibility between fetal and maternal blood types, and prevent alloimmunization.

Placental abruption and neonatal anemia

OBJECTIVE

Placental abruption can cause maternal blood loss and maternal anemia. It is less certain whether abruption can cause fetal blood loss and neonatal anemia.

STUDY DESIGN

Retrospective multi-hospital 24-month analysis of women with placental abruption and their neonates.

RESULTS

Of 55,111 births, 678 (1.2%) had confirmed abruption; 83% of these neonates (564) had one or more hemoglobins recorded in the first day. Four-hundred-seventy (83.3%) had a normal hemoglobin (≥5th% reference interval) while 94 (16.7%) had anemia, relative risk 3.26 (95% CI, 2.66-4.01) vs. >360,000 neonates from previous reference interval reports. The relative risk of severe anemia (<1st% interval) was 4.96 (3.44-7.16). When the obstetrician identified the abruption as "small" or "marginal" the risk of anemia was insignificant.

CONCLUSIONS

Most abruptions do not cause neonatal anemia but approximately 16% do. If an abruption is not documented as small, it is important to surveille the neonate for anemia.

A novel enzyme-linked immunostaining technique based on silk membrane for the prenatal detection of fetomaternal haemorrhage

Objective: Developing a simple, rapid, reliable, sensitive, and cost-effective method for prenatal detection of fetomaternal haemorrhage by combining multi-aperture silk membrane with enzyme-linked immunosorbent assay (ELISA), which does not require any complicated instruments and can be visually colored, so as to provide a new method for clinical detection of fetomaternal haemorrhage. Methods: As a carrier, a chemically treated silk membrane was used to immobilize anti-A/anti-B antibody reagent. PBS washed slowly after vertically dropping red blood cells. After adding biotin-labeled anti-A/anti-B antibody reagent, PBS is slowly washed, enzyme-labeled avidin is added, and TMB is used for color development after washing. Results: When there were both anti-A and anti-B fetal erythrocytes in pregnant women's peripheral blood, the final color was dark brown. When there are no anti-A and anti-B fetal red blood cells in pregnant women's peripheral blood, the final color development results do not change, which corresponds to the color of chemically treated silk membrane. Conclusion: The new enzyme-linked immunosorbent assay (ELISA) based on a silk membrane can distinguish fetal red blood cells from maternal red blood cells prenatally and can be used for prenatal detection of fetomaternal haemorrhage.

Neonatal subgaleal hemorrhage: twenty years of trends in incidence, associations, and outcomes

BACKGROUND

In 2011, we reported 38 neonates with subgaleal hemorrhage (SH), relating an increasing incidence. It is unclear whether the incidence in our hospitals continued to rise and which risk factors and outcomes are associated with this condition.

DESIGN

We retrospectively analyzed every recognized case of SH in our hospitals from the end of our previous report (2010) to the present (2022). We redescribed the incidence, scored severity, tabulated blood products transfused, and recorded outcomes.

RESULTS

Across 141 months, 191 neonates were diagnosed with SH; 30 after vacuum or forceps. The incidence (one/1815 births) was higher than in our 2011 report (one/7124 births). Also, severe SH (requiring transfusion) was more common (one/10,033 births vs. one/20,950 births previously). Four died (all with severe SH) and 12 had neurodevelopmental impairment.

CONCLUSION

Recognized cases of SH are increasing in our system without a clear explanation. Adverse outcomes are rare but continue to occur.

Severe Anemia at Birth-Incidence and Implications

OBJECTIVE

To identify neonates with severe anemia at birth, defined by a hemoglobin or hematocrit value within the first 6 hours after birth that plotted below the 1st percentile according to gestational age. For each patient, we retrospectively determined whether caregivers recognized the anemia within the first 24 hours after birth and the probable cause and outcome of anemia.

STUDY DESIGN

This was a retrospective cohort analysis of Intermountain Healthcare population-based data from neonates born between January 2011 and December 2020 who had a hemoglobin or hematocrit value measured within the first 6 hours after birth below the 1st percentile lower reference interval (hematocrit ∼35% in near-term/term neonates).

RESULT

Among 299 927 live births, we identified 344 neonates with severe anemia at birth. In 191 of these neonates (55.5%), the anemia was recognized by caregivers during the first 24 hours. Anemia was more likely to be recorded as a problem (85%) if the hemoglobin was ≥2 g/dL below the 1st percentile (P < .001). The lowest hemoglobin values occurred in those in whom hemorrhage was the probable cause (P < .013 vs hemolysis and P < .001 vs hypoproduction, mixed cause, or indeterminant.) Treatment was provided to 39.5%. A retrospective review suggested that mixed mechanisms, particularly hemorrhagic plus hemolytic, occurred more commonly than was recognized at the time of occurrence.

CONCLUSIONS

Severe anemia at birth often went unrecognized on the first day of life. Algorithm-directed retrospective reviews commonly identified causes that were not listed in the medical record. We postulate that earlier recognition and more accurate diagnoses would be facilitated by an electronic medical record-associated hemoglobin/hematocrit gestational age nomogram.