ABSTRACT
BackgroundPregnant persons are at increased risk of severe COVID-19 and adverse obstetric outcomes. Understanding maternal antibody response and transplacental transfer after SARS-CoV-2 infection and COVID-19 vaccination is important to inform public health recommendations. MethodsThis prospective observational cohort study included 351 birthing individuals who had SARS-CoV-2 infection or COVID-19 vaccination during pregnancy. IgG and IgM to SARS-CoV-2 S1 receptor binding domain were measured in maternal and cord blood. Antibody levels and transplacental transfer ratios were compared across 1) disease severity for those with SARS-CoV-2 infection and 2) infection versus vaccination. FindingsThere were 252 individuals with SARS-CoV-2 infection and 99 who received COVID-19 vaccination during pregnancy. Birthing people with more severe SARS-CoV-2 infection category had higher maternal and cord blood IgG levels (p=0.0001, p=0.0001). Median IgG transfer ratio was 0.87-1.2. Maternal and cord blood IgG were higher after vaccination than infection (p=0.001, p=0.001). Transfer ratio was higher after 90 days in the vaccinated group (p<0.001). Modeling showed higher amplitude and half-life of maternal IgG following vaccination (p<0.0001). There were no significant differences by fetal sex. InterpretationCOVID-19 vaccination in pregnancy leads to higher and longer lasting maternal IgG levels, higher cord blood IgG, and higher transfer ratio after 90 days compared to SARS-CoV-2 infection. Greater infection severity leads to higher maternal and cord blood antibodies. Maternal IgG decreases over time following both vaccination and infection, reinforcing the importance of vaccination, even after infection, and vaccine boosters for pregnant patients.
ABSTRACT
ObjectivesTo describe histopathologic findings in the placentas of women with COVID-19 during pregnancy. MethodsPregnant women with COVID-19 delivering between March 18, 2020 and May 5, 2020 were identified. Placentas were examined and compared to historical controls and women with placental evaluation for a history of melanoma. Results16 placentas from patients with SARS-CoV-2 were examined (15 with live birth in the 3rd trimester 1 delivered in the 2nd trimester after intrauterine fetal demise). Compared to controls, third trimester placentas were significantly more likely to show at least one feature of maternal vascular malperfusion (MVM), including abnormal or injured maternal vessels, as well as delayed villous maturation, chorangiosis, and intervillous thrombi. Rates of acute and chronic inflammation were not increased. The placenta from the patient with intrauterine fetal demise showed villous edema and a retroplacental hematoma. ConclusionsRelative to controls, COVID-19 placentas show increased prevalence of features of maternal vascular malperfusion (MVM), a pattern of placental injury reflecting abnormalities in oxygenation within the intervillous space associated with adverse perinatal outcomes. Only 1 COVID-19 patient was hypertensive despite the association of MVM with hypertensive disorders and preeclampsia. These changes may reflect a systemic inflammatory or hypercoagulable state influencing placental physiology. Key PointsO_LIThe placentas of women infected with SARS-CoV2 have higher rates maternal vascular malperfusion features compared to controls. C_LIO_LIMaternal vascular malperfusion has been associated with adverse perinatal outcomes, such as preeclampsia, fetal growth restriction, preterm birth, and stillbirth. C_LIO_LIAs the placentas of women with SARS-CoV2 show reproducible histopathologic abnormalities, these findings suggest increased antenatal surveillance for women with COVID-19 may be warranted. C_LI
