Kinetics of Maternally Derived Anti-Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Antibodies in Infants in Relation to the Timing of Antenatal Vaccination.

BACKGROUND: SARS-CoV-2 infection during early infancy can result in severe disease. We evaluated the durability of maternally-derived anti-SARS-CoV-2 antibodies in infants and its relation to antenatal vaccination timing. METHODS: Sera were prospectively collected at birth and 3 months after delivery from mother-infant pairs following antenatal BNT162b2 vaccination. SARS-CoV-2 receptor binding domain (RBD)-specific IgG levels and neutralizing activity were evaluated. RESULTS: 56 mother-infant pairs were included: 15 (26.8%) were vaccinated in the first trimester, 16 (28.6%) in the second trimester, and 25 (44.6%) in the third trimester.At the time of delivery, all neonates were positive for anti-RBD-specific IgG with a median concentration of 4046 [IQR 2446-7896] AU/mL, with the highest concentration found after third trimester vaccination (median 6763 [IQR 3857-12561] AU/mL). At 3 months after delivery, anti RBD-specific IgG levels in infants significantly waned with a median concentration of 545 [IQR 344-810] AU/mL (P < .001). The half-life of anti-RBD-specific IgG was 66 days among mothers and 30 days among infants. While at the time of delivery, all neonates had detectable neutralizing activity regardless of gestational age at vaccination, at 3-months of age, a higher proportion of infants born to mothers vaccinated in third trimester had persistent neutralizing activity as compared to those born to mothers vaccinated in second trimester. CONCLUSIONS: Maternal vaccination leads to efficient transplacental antibody transfer, with persistent anti-SARS-CoV-2 antibodies detected at 3 months of age in all infants. The observed effect of antenatal immunization timing on the kinetics of maternally-derived antibodies may have implications for SARS-CoV-2 vaccination strategies.

Maternal and Neonatal Severe Acute Respiratory Syndrome Coronavirus 2 Omicron Variant Neutralization After Antenatal Messenger RNA Vaccination.

We evaluated the neutralization efficiency against SARS-CoV-2 Omicron variant in maternal and cord blood sera after antenatal BNT162b2 vaccination. Neutralizing antibodies against Omicron were lacking at the time of delivery after 2-dose vaccination. A third booster dose was essential in building neutralizing antibody capacity against Omicron among mothers and neonates.

The Effect of Gestational Age at BNT162b2 mRNA Vaccination on Maternal and Neonatal Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Antibody Levels.

BACKGROUND: Coronavirus disease 2019 (COVID-19) during pregnancy and early infancy can result in severe disease. Evaluating the effect of gestational age at the time of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination on maternal antibody levels and transplacental antibody transfer has important implications for maternal care and vaccination strategies. METHODS: Maternal and cord blood sera were collected from mother-newborn dyads (n = 402), following term delivery after antenatal 2-dose SARS-CoV-2 BNT162b2 mRNA vaccination. SARS-CoV-2 spike protein (S) and receptor binding domain (RBD)-specific IgG levels were evaluated in the samples collected. RESULTS: Median anti-S and anti-RBD-specific IgG levels in maternal sera at the time of delivery were lowest following first-trimester vaccination (n = 90; anti-S IgG: 76 AU/mL; anti-RBD-specific IgG: 478 AU/mL), intermediate in those vaccinated in the second trimester (n = 124; anti-S IgG: 126 AU/mL; anti-RBD-specific IgG: 1263 AU/mL), and highest after third-trimester vaccination (n = 188; anti-S IgG: 240 AU/mL; anti-RBD-specific IgG: 5855 AU/mL). Antibody levels in neonatal sera followed a similar pattern and were lowest following antenatal vaccination in the first trimester (anti-S IgG: 126 AU/mL; anti-RBD-specific IgG: 1140 AU/mL). In a subgroup of parturients vaccinated in the first trimester (n = 30), a third booster dose was associated with significantly higher maternal and neonatal antibody levels. CONCLUSIONS: These results suggest a considerable antibody waning throughout pregnancy in those vaccinated at early gestation. The observed boosting effect of a third vaccine dose hints at its potential benefit in those who completed the 2-dose vaccine series at early pregnancy or before conception. The impact of antenatal immunization timing on SARS-CoV-2 transplacental antibody transfer may influence neonatal seroprotection.

Duration of the second stage of labour and risk of subsequent spontaneous preterm birth.

OBJECTIVES: To determine the risk of spontaneous preterm birth (sPTB) associated with the length of second stage of labour in the first term delivery. DESIGN: Retrospective cohort study. SETTING: University hospital. POPULATION: Women with first two consecutive singleton births and the first birth at term. Those who did not reach the second stage of labour in the first delivery were excluded. METHODS: Charts from 2007 to 2019 were reviewed. MAIN OUTCOME MEASURES: Rate of sPTB (<37 weeks of gestation) in the second delivery. RESULTS: Of 13 958 women who met study inclusion criteria, 1464 (10.5%) parturients had a prolonged second stage (≥180 min) in their first term delivery. The rate of sPTB in the second delivery was similar in those with and without a prolonged second stage in first delivery (2.8% versus 2.8%; adjusted odds ratio [aOR] 1.35, 95% CI 0.96-1.90). After adjustment for mode of delivery, prolonged second stage was also not associated with subsequent sPTB in those who delivered by spontaneous and operative vaginal delivery. Those delivered by second-stage caesarean section in the first delivery had a higher risk of sPTB in the second delivery (25/526, 4.8%; aOR 2.66, 95% CI 1.71-4.12; p < 0.001), with a more pronounced risk in those with second-stage caesarean following a prolonged second stage of labour (15/259, 5.8%; aOR 3.40, 95% CI 1.94-5.94; p < 0.001). CONCLUSION: Second-stage duration in a first term vaginal delivery is not associated with subsequent sPTB. The risk of sPTB is increased following second-stage caesarean section, particularly if performed after a prolonged second stage. TWEETABLE ABSTRACT: Second-stage caesarean delivery, particularly after prolonged second stage, increases the risk of preterm birth.

Efficient Maternofetal Transplacental Transfer of Anti- Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Spike Antibodies After Antenatal SARS-CoV-2 BNT162b2 Messenger RNA Vaccination.

Maternal and cord blood sera were collected from 20 parturients who received the BNT162b2 vaccine. All women and infants were positive for anti S- and anti-receptor binding domain antibody-specific immunoglobulin G. Cord blood antibody concentrations were correlated to maternal levels and to time since vaccination. Antenatal severe acute respiratory syndrome coronavirus 2 vaccination may provide maternal and neonatal protection.

Conservative management of Caesarean scar pregnancies with systemic multidose methotrexate: predictors of treatment failure and reproductive outcomes.

RESEARCH QUESTION: Caesarean scar pregnancy (CSP) is an increasing concern in modern obstetrics. Early diagnosis and management are of utmost importance. The optimal management approach for CSP is not well established, with various treatment modalities reported. The role of conservative management of CSP has been previously reported, with conflicting results. This study aimed to further evaluate its role and better delineate the subsequent reproductive outcomes. DESIGN: A retrospective cohort study including all patients diagnosed with a CSP and treated by intention of conservative management with systemic methotrexate (MTX). Maternal and gestation characteristics were compared between treatment success and failure groups. RESULTS: Thirty-six cases of CSP were encountered. Overall, 29/36 (80.6%) were treated by systemic injection of MTX while the other 19.4% had combined systemic and local (i.e. intra-sac) MTX treatment. Invasive intervention was needed in five (13.9%) cases (failure group). Among those successfully treated with MTX, the median time to resolution was 22 (interquartile range 13-37) days. Cases who were converted to surgical treatment had a higher number of previous Caesarean deliveries (median 4 versus 2, P = 0.002). In logistic regression modelling, the number of previous Caesarean deliveries was the only factor independently associated with conversion to surgical management (odds ratio 2.02, 95% confidence interval 1.03-3.94). The majority of future pregnancies ended at term pregnancy with only one preterm delivery due to severe intrauterine growth restriction. CONCLUSIONS: Systemic MTX therapy is a safe and effective strategy for the treatment of CSP, with favourable subsequent reproductive results and a low conversion rate to surgical management.

Factors associated with the development of neonatal hypoglycemia after antenatal corticosteroid administration: It's all about timing.

OBJECTIVE: To determine the factors associated with neonatal hypoglycemia among neonates exposed to antenatal corticosteroid (ACS). METHODS: A retrospective study conducted during 2017-2019 at a tertiary-care center including all neonates delivered between 24 and 34 weeks of gestation after ACS administration. The primary outcome was neonatal hypoglycemia (<40 mg/dl). RESULTS: Overall, 362 early preterm neonates, including 205 singletons and 157 twins, were exposed to ACS before delivery and constituted the study group. Of them, 275 (76.0%) were exposed to a single ACS course and 87 (24.0%) to an additional rescue ACS course. Neonatal hypoglycemia occurred in 84 (23.2%) neonates. The incidence of neonatal hypoglycemia was significantly higher in those delivered between 24 and 48 h after ACS administration compared with those delivered outside this time interval (10/25, 40.0% vs 74/337, 21.9%; P = 0.049). In multivariate analysis, after adjusting for neonatal birth weight and gestational age, delivery within 24-48 h after ACS administration was the only independent risk factor associated with neonatal hypoglycemia (adjusted odds ratio 2.41, 95% confidence interval 1.03-5.68; P = 0.044). CONCLUSION: Neonatal hypoglycemia occurred in over one-fifth of those exposed to ACS, and was independently associated with delivery between 24 and 48 h after ACS administration.

Rescue antenatal corticosteroids and neonatal outcomes in twin gestation.

OBJECTIVE: Although repeated antenatal corticosteroids (ACS) courses are not recommended, a single rescue ACS course has been shown to decrease neonatal morbidity among preterm singletons. However, little is known regarding the effects of rescue ACS course in twin pregnancies. METHODS: A retrospective cohort study conducted during 2015-2017 at a tertiary-care center including all twins delivered between 24-34 weeks of gestation who received at least one course of ACS. RESULTS: Overall, 162 (70.4%) twins were exposed to a single ACS course and 68 (29.6%) to an additional rescue ACS course. Rescue ACS course was associated with lower rates of respiratory distress syndrome (7.4% vs. 19.1%, p = .03), surfactant use (7.4% vs 18.5%, p = .04) and bronchopulmonary dysplasia (0 vs 8.6%, p = .01) as compared to a single ACS course. In the rescue ACS group, compared to the single ACS group, the rates of composite respiratory adverse outcome (10.3% vs 22.2%, OR [95% CI]: 0.40 (0.17-0.95), p = .04) and any adverse neonatal outcome (13.2% vs 26.5%, OR [95% CI]: 0.42 (0.19-0.92), p = .04) were significantly lower. Hospital stay was also shorter among neonates born to mothers receiving a rescue ACS course (median 23 vs. 30 days, p = .01). No differences were noted in neonatal birthweight, head circumference and the rate of neonatal hypoglycemia. CONCLUSION: Rescue ACS course was associated with improved respiratory and neonatal outcomes in twin gestations. Further studies are warranted to confirm our findings and better delineate the optimal regimen of rescue ACS in this setting.

Timing of SARS-CoV-2 vaccination during the third trimester of pregnancy and transplacental antibody transfer: a prospective cohort study.

OBJECTIVE: We aimed to assess the impact of early versus late third-trimester maternal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination on transplacental transfer and neonatal levels of SARS-CoV-2 antibodies. METHODS: Maternal and cord blood sera were collected following term delivery after antenatal SARS-CoV-2 BNT162b2 mRNA vaccination, with the first vaccine dose administered between 27 and 36 weeks of gestation. SARS-CoV-2 spike protein (S) and receptor-binding domain (RBD) -specific, IgG levels and neutralizing potency were evaluated in maternal and cord blood samples. RESULTS: The study cohort consisted of 171 parturients-median age 31 years (interquartile range (IQR) 27-35 years); median gestational age 39+5 weeks (IQR 38+5-40+4 weeks)-83 (48.5%) were immunized in early thrird-trimester (first dose at 27-31 weeks) and 88 (51.5%) were immunized in late third trimester (first dose at 32-36 weeks). All mother-infant paired sera were positive for anti S- and anti-RBD-specific IgG. Anti-RBD-specific IgG concentrations in neonatal sera were higher following early versus late third-trimester vaccination (median 9620 AU/mL (IQR 5131-15332 AU/mL) versus 6697 AU/mL (IQR 3157-14731 AU/mL), p 0.02), and were positively correlated with increasing time since vaccination (r = 0.26; p 0.001). Median antibody placental transfer ratios were increased following early versus late third-trimester immunization (anti-S ratio: 1.3 (IQR 1.1-1.6) versus 0.9 (IQR 0.6-1.1); anti-RBD-specific ratio: 2.3 (IQR 1.7-3.0) versus 0.7 (IQR 0.5-1.2), p < 0.001). Neutralizing antibodies placental transfer ratio was greater following early versus late third-trimester immunization (median 1.9 (IQR 1.7-2.5) versus 0.8 (IQR 0.5-1.1), p < 0.001), and was positively associated with longer duration from vaccination (r = 0.77; p < 0.001). CONCLUSIONS: Early compared with late third-trimester maternal SARS-CoV-2 immunization enhanced transplacental antibody transfer and increased neonatal neutralizing antibody levels. Our findings highlight that vaccination of pregnant women early in the third trimester may enhance neonatal seroprotection.

Clinical and molecular epidemiology of Acinetobacter baumannii bloodstream infections in an endemic setting.

AIM: The transmission dynamics of Acinetobacter baumannii in endemic settings, and the relation between microbial properties and patients' clinical outcomes, are yet obscure and hampered by insufficient metadata. METHODS & RESULTS: Of 20 consecutive patients with A. baumannii bloodstream infection that were thoroughly analyzed at a single center, at least one transmission opportunity was evident for 85% of patients. This implies that patient-to-patient transmission is the major mode of A. baumannii acquisitions in health facilities. Moreover, all patients who died immediately (<24 h of admission) were infected with a single clone (ST457; relative risk = 1.6; p = 0.05). CONCLUSION: This preliminary analysis should prompt further investigation by mapping genomic virulence determinants among A. baumannii ST457 lineage compared with other strains.