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 3600 g v 3680 g, 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 and the emerging Delta variant) and the severity and timing of infection on the developing fetus.
Subject(s)
Blood Coagulation Disorders , COVID-19 , Fetal Blood , Pregnancy Complications, Infectious , Case-Control Studies , Female , Humans , Placenta , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Pregnancy Outcome , Prospective Studies , RNA, Viral , SARS-CoV-2ABSTRACT
BACKGROUND: Background Population-based data on SARS-CoV-2 infection in pregnancy and assessment of passive immunity to the neonate, is lacking. We profiled the maternal and fetal response using a combination of viral RNA from naso-pharyngeal swabs and serological assessment of antibodies against SARS-CoV-2. METHODS: This multicentre prospective observational study was conducted between March 24th and August 31st 2020. Two independent cohorts were established, a symptomatic SARS-CoV-2 cohort and a cohort of asymptomatic pregnant women attending two of the largest maternity hospitals in Europe. Symptomatic women were invited to provide a serum sample to assess antibody responses. Asymptomatic pregnant women provided a nasopharyngeal swab and serum sample. RT-PCR for viral RNA was performed using the Cobas SARS-CoV-2 6800 platform (Roche). Umbilical cord bloods were obtained at delivery. Maternal and fetal serological response was measured using both the Elecsys® Anti-SARS-CoV-2 immunoassay (Roche), Abbott SARS-CoV-2 IgG Assay and the IgM Architect assay. Informed written consent was obtained from all participants. RESULTS: Ten of twenty three symptomatic women had SARS-CoV-2 RNA detected on nasopharyngeal swabs. Five (5/23, 21.7%) demonstrated serological evidence of anti-SARS-CoV-2 IgG antibodies and seven (30.4%, 7/23) were positive for IgM antibodies. In the asymptomatic cohort, the prevalence of SARS-CoV-2 infection in RNA was 0.16% (1/608). IgG SARS-CoV-2 antibodies were detected in 1·67% (10/598, 95% CI 0·8%-3·1%) and IgM in 3·51% (21/598, 95% CI 2·3-5·5%). Nine women had repeat testing post the baseline test. Four (4/9, 44%) remained IgM positive and one remained IgG positive. 3 IgG anti-SARS-CoV-2 antibodies were detectable in cord bloods from babies born to five seropositive women who delivered during the study. The mean gestation at serological test was 34 weeks. The mean time between maternal serologic positivity and detection in umbilical cord samples was 28 days. CONCLUSION: Using two independent serological assays, we present a comprehensive illustration of the antibody response to SARS-CoV-2 in pregnancy, and show a low prevalence of asymptomatic SARS-CoV2. Transplacental migration of anti-SARS-CoV-2 antibodies was identified in cord blood of women who demonstrated antenatal anti-SARS-CoV-2 antibodies, raising the possibility of passive immunity.
Subject(s)
COVID-19/diagnosis , COVID-19/immunology , Delivery, Obstetric , SARS-CoV-2/immunology , Antibody Formation/immunology , COVID-19/genetics , COVID-19/virology , Female , Fetal Blood/metabolism , Follow-Up Studies , Humans , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Longitudinal Studies , Pregnancy , Prospective StudiesABSTRACT
Pregnant women may be at higher risk of severe complications associated with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which may lead to obstetrical complications. We performed a case control study comparing pregnant women with severe coronavirus disease 19 (cases) to pregnant women with a milder form (controls) enrolled in the COVI-Preg international registry cohort between March 24 and July 26, 2020. Risk factors for severity, obstetrical and immediate neonatal outcomes were assessed. A total of 926 pregnant women with a positive test for SARS-CoV-2 were included, among which 92 (9.9%) presented with severe COVID-19 disease. Risk factors for severe maternal outcomes were pulmonary comorbidities [aOR 4.3, 95% CI 1.9-9.5], hypertensive disorders [aOR 2.7, 95% CI 1.0-7.0] and diabetes [aOR2.2, 95% CI 1.1-4.5]. Pregnant women with severe maternal outcomes were at higher risk of caesarean section [70.7% (n = 53/75)], preterm delivery [62.7% (n = 32/51)] and newborns requiring admission to the neonatal intensive care unit [41.3% (n = 31/75)]. In this study, several risk factors for developing severe complications of SARS-CoV-2 infection among pregnant women were identified including pulmonary comorbidities, hypertensive disorders and diabetes. Obstetrical and neonatal outcomes appear to be influenced by the severity of maternal disease.