Haematological parameters and coagulation in umbilical cord blood following COVID-19 infection in pregnancy

Abstract

Objective The aim of this study was to evaluate infants, born to women with SARS-CoV-2 detected during pregnancy, for evidence of haematological abnormalities or hypercoagulability in umbilical cord blood. Study Design: This was a prospective observational case-control study of infants born to women who had SARS-CoV-2 RNA detected by PCR at any time during their pregnancy (n=15). The study was carried out in a Tertiary University Maternity Hospital (8,500 deliveries/year) in Ireland. This study was approved by the Hospital Research Ethics Committee and written consent was obtained. Umbilical cord blood samples were collected at delivery, full blood count and Calibrated Automated Thrombography were performed. Demographics and clinical outcomes were recorded. Healthy term infants, previously recruited as controls to a larger study prior to the outbreak of COVID-19, were the historical control population (n=10). Results Infants born to women with SARS-CoV-2 had similar growth parameters (birth weight 3600g v 3680g, p=0.83) and clinical outcomes to healthy controls, such as need for resuscitation at birth (2 (13.3%) v 1 (10%), p=1.0) and NICU admission (1 (6.7%) v 2 (20%), p=0.54). Haematological parameters (Haemoglobin, platelet, white cell and lymphocyte counts) in the COVID-19 group were all within normal neonatal reference ranges. Calibrated Automated Thrombography revealed no differences in any thrombin generation parameters (lag time (p=0.92), endogenous thrombin potential (p=0.24), peak thrombin (p=0.44), time to peak thrombin (p=0.94)) between the two groups. Conclusion: In this prospective study including eligible cases in a very large population of approximately 1500 women, there was no evidence of derangement of the haematological parameters or hypercoagulability in umbilical cord blood due to COVID-19. Further research is required to investigate the pathological placental changes, particularly COVID-19 placentitis and the impact of different strains of SARS-CoV-2 (particularly the B.1.1.7 variant) and the severity and timing of infection on the developing fetus.

Transplacental Transfer of SARS-CoV-2 Receptor-Binding Domain IgG Antibodies from Mothers to Neonates in a Cohort of Pakistani Unvaccinated Mothers

“…We also did not observe any difference between the hematological parameters of seropositive and seronegative mothers. Similar findings were reported by Murphy et al in their study on neonates born to mothers following COVID-19 infection in pregnancy [ 4 ].…”

“…Pregnant women are at a higher risk of morbidity and mortality due to systemic infections compared to non-pregnant women of the same age [ 2 ]. Due to its systemic nature and associated severity, COVID-19 infection has been shown to impact fetal and neonatal development with undesirable outcomes such as the increased risk of abortion, preterm delivery, low birth weight, and stillbirth [ 3 , 4 ]. The mechanism of such complications can be due to various reasons.…”

Comparative Analysis of Hematological and Biochemical Changes in Neonates among Women with and without COVID-19 Infection during Pregnancy

“…However, there is no evidence of an association of COVID-19 with fetal anemia. In addition, the hemoglobin level of the umbilical cord blood of newborns from COVID-19-positive mothers has been reported to be in the normal range [ 15 ]. This suggests that COVID-19 infection during pregnancy does not directly impact fetal hemoglobin levels.…”

“…These changes occur even in the absence of inflammatory changes or confirmed placental infection. It is possible that these placental changes are a result of a maternal systemic hypercoagulable or hyperinflammatory state following COVID-19 infection [ 13 , 14 , 15 ]. Platelets are crucial factors in promoting inflammation, and their role in viral infection-mediated thrombosis is well known [ 16 , 17 ].…”