Maternal and Neonatal Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Immunoglobulin G Levels After the Pfizer-BioNTech Booster Dose for Coronavirus Disease 2019 (COVID-19) Vaccination During the Second Trimester of Pregnancy.

OBJECTIVE: To evaluate maternal and neonatal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) antibody levels at birth after a third (booster) dose of the Pfizer-BioNTech messenger RNA (Pfizer) coronavirus disease 2019 (COVID-19) vaccine during the second trimester of pregnancy, and compare them with those in women who received two vaccine doses during the second trimester. METHODS: We conducted a prospective cohort study of women admitted to the delivery ward at a single center who received the third Pfizer COVID-19 vaccine dose (booster group) at 17-30 weeks of pregnancy and who did not have previous SARS-CoV-2 infection. Maternal and neonatal antibody levels were measured on admission for delivery and in the umbilical cord blood after birth. Antibody levels for the booster group were compared with those in a historical control group of pregnant women who received their second vaccine dose (two-dose group) within the same gestational age window. RESULTS: Between October 2021 and February 2022, antibody levels were measured in 121 women and 109 neonates at a mean±SD of 15.3±3.9 weeks after booster vaccination. Neonatal titers measured two times higher than maternal titers, with inverse correlation between maternal and neonatal titers at birth and time interval from third vaccination. The two-dose group included 121 women and 107 neonates, with antibody levels measured at a mean±SD of 14.6±2.6 weeks after the second dose. Median [interquartile range] maternal antibody titers were higher in the booster group (4,485 [2,569-9,702] AU/mL) compared with the two-dose group (1,122 [735-1,872] AU/mL) (P<.001). Furthermore, neonatal antibody titers were higher in the booster group (8,773 [5,143-18,830] AU/mL) compared with the two-dose group (3,280 [2,087-5,754] AU/mL) (P<.001). CONCLUSION: Maternal and neonatal SARS-CoV-2 IgG antibody titers after second-trimester maternal Pfizer COVID-19 vaccination were significantly higher after the booster dose compared with the two-dose vaccination series. Although there is uncertainty as to whether antibody levels correlate with protection, these data support the importance of booster vaccination during pregnancy to restore maternal and neonatal protection against COVID-19.

Third trimester messenger RNA COVID-19 booster vaccination upsurge maternal and neonatal SARS-CoV-2 immunoglobulin G antibody levels at birth.

OBJECTIVE: BNT162b2 messenger RNA (mRNA) COVID-19 vaccine administered during pregnancy was found to produce a strong maternal immunoglobulin (IgG) response which crosses the placenta to the newborn. Our aim was to evaluate maternal and neonatal SARS-CoV-2 IgG antibody levels at birth, following a COVID-19 booster vaccine during the third trimester. STUDY DESIGN: A prospective cohort study including women admitted to delivery ward at least 7 days after their BNT162b2 (Pfizer/BioNTech) booster vaccination without a prior clinical COVID-19 infection. SARS-CoV-2 IgG antibodies levels were measured in maternal blood upon admission to delivery and in the umbilical blood within 30 min following delivery. The correlation between antibody titers, feto-maternal characteristics, maternal side effects following vaccination, and time interval from vaccination to delivery were analyzed. RESULTS: Between September to November 2021, high antibody levels were measured in all 102 women and 93 neonatal blood samples, at a mean ± standard deviation duration of 7.0 ± 2.9 weeks after the third vaccine. We found positive correlation between maternal and neonatal antibodies (r = 0.73, 95% confidence interval [CI] 0.61 to 0.81, p < 0.001), with neonatal titers approximately 1.4 times higher compared to maternal titers. In the multivariable analysis maternal antibody levels dropped by -7.2% (95% CI -12.0 to -2.3%, p = 0.005) for each week that passed since the receipt of the third vaccine dose. In contrary, systemic side effects after the third vaccine were associated with higher maternal antibody levels of 52.0% (95% CI 4.7 to 120.8%, p = 0.028). Also, for each 1 unit increase in maternal body mass index, maternal antibody levels increased by 3.6% (95% CI 0.4 to 6.9%, p = 0.025). CONCLUSIONS: BNT162b2 mRNA COVID-19 booster dose during the third trimester of pregnancy was associated with strong maternal and neonatal responses as reflected by maternal and neonatal SARS-CoV-2 IgG antibody levels measured at birth. These findings support the administration of the COVID-19 booster to pregnant women to restore maternal and neonatal protection during the ongoing pandemic.

Consequences of the COVID-19 pandemic on the postpartum course: Lessons learnt from a large-scale comparative study in a teaching hospital.

OBJECTIVE: To evaluate the consequences of COVID-19 pandemic restrictions on the postpartum course. METHODS: A retrospective cross-sectional study compared women who gave birth between March and April 2020 (first wave), between July to September 2020 (second wave), and a matched historical cohort throughout 2017-2019 (groups A, B, and C, respectively). Primary outcomes were postpartum length of stay (LOS), presentations to the emergency department (ED), and readmissions 30 days or longer after discharge. Following Bonferroni correction, p < 0.016 was considered statistically significant. RESULTS: In total, 3377 women were included: 640, 914, and 1823 in groups A, B, and C, respectively. LOS after birth (both vaginal and cesarean) was shorter in groups A and B compared to the control group (2.28 ± 1.01 and 2.25 ± 0.93 vs 2.55 ± 1.10 days, p < 0.001). Rates of ED presentations 30 days after discharge were higher in groups C and B compared to group A (6.63% and 6.45% vs 3.12%, p = 0.006). Rates of readmissions 30 days after discharge were 0.78%, 1.42%, and 1.09% (groups A, B, and C, respectively), demonstrating no statistical difference (p = 0.408). CONCLUSION: During the COVID-19 pandemic, there was a reduction or no change in rates of ED presentations and readmissions, despite the shortened LOS after delivery. A shift in policy regarding the postpartum LOS could be considered.