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.

Maternal and Neonatal SARS-CoV-2 Immunoglobulin G Antibody Levels at Delivery After Receipt of the BNT162b2 Messenger RNA COVID-19 Vaccine During the Second Trimester of Pregnancy.

IMPORTANCE: BNT162b2 messenger RNA (mRNA) COVID-19 vaccination in the third trimester was found to be associated with a strong maternal humoral IgG response that crossed the placenta and approached maternal titers in the newborn. OBJECTIVE: To evaluate maternal and neonatal SARS-CoV-2 immunoglobulin G (IgG) antibody levels at birth after mRNA COVID-19 vaccination during the second trimester of pregnancy. DESIGN, SETTING, AND PARTICIPANTS: This prospective cohort study, conducted at a single medical center in Haifa, Israel, from May to July 2021, included women with a singleton pregnancy over 24 weeks of gestation at least 7 days after receipt of their second COVID-19 vaccine dose who were not known to be previously infected with COVID-19. EXPOSURES: BNT162b2 (Pfizer/BioNTech) vaccination. MAIN OUTCOMES AND MEASURES: The primary outcomes were SARS-CoV-2 IgG antibody titers measured in the parturient at admission and in the umbilical cord blood within 30 minutes after delivery. Secondary outcomes were the correlation between antibody titers, feto-maternal characteristics, maternal adverse effects after vaccination, and time interval from vaccination to delivery. RESULTS: Antibody levels were measured for 129 women (mean [SD] age, 31.9 [4.9] years) and 114 neonates, with 100% of the tests having positive results. The mean (SD) gestational age at administration of the second vaccine dose was 24.9 (3.3) weeks. Neonatal IgG titers were 2.6 times higher than maternal titers (median [range], 3315.7 [350.1-17 643.5] AU/mL vs 1185.2 [146.6-32 415.1] AU/mL). A positive correlation was demonstrated between maternal and neonatal antibodies (r = 0.92; 95% CI, 0.89-0.94). Multivariable analysis revealed that for each week that passed since receipt of the second vaccine dose, maternal and neonatal antibody levels changed by -10.9% (95% CI, -17.2% to -4.2%; P = .002) and -11.7% (95% CI, -19.0 to -3.8%; P = .005), respectively. For each 1-year increase in the mother's age, maternal and neonatal antibody levels changed by -3.1% (95% CI, -5.3% to -0.9%; P = .007) and -2.7% (95% CI, -5.2% to -0.1%; P = .04), respectively. CONCLUSIONS AND RELEVANCE: In this cohort study, receipt of the BNT162b2 mRNA COVID-19 vaccine during the second trimester of pregnancy was associated with maternal and neonatal humoral responses, as reflected in maternal and neonatal SARS-CoV-2 IgG antibody levels measured after delivery. These findings support COVID-19 vaccination of pregnant individuals during the second trimester to achieve maternal protection and newborn safety during the pandemic.

Changes in the obstetrical emergency department profile during the COVID-19 pandemic.

BACKGROUND: The COVID-19 outbreak caused persons to be reluctant to seek medical care due to fear of contracting the infection. OBJECTIVES: To evaluate the effect of the COVID-19 pandemic on admission rates to the delivery room and the feto-maternal unit, and to assess the effect on the nature of presenting obstetrical complaints to the emergency department. STUDY DESIGN: A retrospective cohort study in one medical center. The population was women > 20 weeks pregnant who presented to the obstetrical emergency department with self-complaints during 29 days at the peak of the pandemic outbreak, and a matched group during the exact period in the previous year. We compared between the groups: clinical, obstetrical, and demographic data, including age, area of residence, gravidity, parity, previous cesarean deliveries, high-risk pregnancy follow-up, the last 30 days admissions to the obstetrical emergency department, gestational age, chief complaints, cervical dilatation, cervical effacement, admissions to the delivery room or feto-maternal unit, time from admissions to the delivery room to birth, if applicable, and acute obstetrical complications diagnosed at the emergency department. RESULTS: During the pandemic outbreak, 398 women met study inclusion criteria, compared to 544 women in the matched period of the previous year. During the COVID-19 period, women visited the obstetrical emergency department at a more advanced mean gestational age (37.6 ± 3.7 vs. 36.7 ± 4.6, p = .001). Higher proportions of women in the COVID-19 cohort presented in active labor, defined by cervical dilation of at least 5 cm on admission to the labor ward [37 (9.3%) vs 28 (5.1%), p = .013)] and with premature rupture of membranes [82 (20.6%) vs 60 (11.0%), p < .001)], and consequently with more admissions to the delivery room [198 (49.7%) vs 189 (34.7%), p < .001)]. We also recorded a significant increase in urgent obstetrical events in the emergency department during the recorded COVID-19 pandemic [23 (5.8%) vs 12 (2.2%)), p = .004]. However, the rates of neonatal and maternal morbidity did not change. During the outbreak the proportion of visits during the night was higher than during the matched period of the previous year: [138 (34.7%) vs 145 (26.6%)), p = .008]. In a multivariate logistic regression, the higher rates of admission to the delivery room during active labor and of urgent events during the pandemic outbreak compared to the matched period in the previous year remained statistically significant. CONCLUSIONS: The pandemic outbreak of COVID-19 caused a behavioral change among women who presented to the obstetrical emergency department. This was characterized by delayed arrival to the obstetrical emergency department and the delivery room, which led to a significant increase in urgent and acute interventions. The change in behavior did not affect the rates of maternal and neonatal morbidity.