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Cited by 699SARS-CoV-2 and COVID-19 ResearchCOVID-19 Impact on ReproductionVaccine Coverage and Hesitancy

Coronavirus disease 2019 vaccine response in pregnant and lactating women: a cohort study

Open access
Gray, Kathryn J., Bordt, Evan A., Atyeo, Caroline, Deriso, Elizabeth, Akinwunmi, Babatunde, Young, Nicola, Baez, Aranxta Medina, Shook, Lydia L. +13 more·2021·American Journal of Obstetrics and Gynecology
DOI 10.1016/j.ajog.2021.03.023PMC PMC7987048

Published version of a preprint

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Abstract

BACKGROUND: Pregnant and lactating women were excluded from initial coronavirus disease 2019 vaccine trials; thus, data to guide vaccine decision making are lacking. OBJECTIVE: This study aimed to evaluate the immunogenicity and reactogenicity of coronavirus disease 2019 messenger RNA vaccination in pregnant and lactating women compared with: (1) nonpregnant controls and (2) natural coronavirus disease 2019 infection in pregnancy. STUDY DESIGN: A total of 131 reproductive-age vaccine recipients (84 pregnant, 31 lactating, and 16 nonpregnant women) were enrolled in a prospective cohort study at 2 academic medical centers. Titers of severe acute respiratory syndrome coronavirus 2 spike and receptor-binding domain immunoglobulin G, immunoglobulin A, and immunoglobulin M were quantified in participant sera (n=131) and breastmilk (n=31) at baseline, at the second vaccine dose, at 2 to 6 weeks after the second vaccine, and at delivery by Luminex. Umbilical cord sera (n=10) titers were assessed at delivery. Titers were compared with those of pregnant women 4 to 12 weeks from the natural infection (n=37) by enzyme-linked immunosorbent assay. A pseudovirus neutralization assay was used to quantify neutralizing antibody titers for the subset of women who delivered during the study period. Postvaccination symptoms were assessed via questionnaire. Kruskal-Wallis tests and a mixed-effects model, with correction for multiple comparisons, were used to assess differences among groups. RESULTS: Vaccine-induced antibody titers were equivalent in pregnant and lactating compared with nonpregnant women (pregnant, median, 5.59; interquartile range, 4.68-5.89; lactating, median, 5.74; interquartile range, 5.06-6.22; nonpregnant, median, 5.62; interquartile range, 4.77-5.98, P=.24). All titers were significantly higher than those induced by severe acute respiratory syndrome coronavirus 2 infection during pregnancy (P<.0001). Vaccine-generated antibodies were present in all umbilical cord blood and breastmilk samples. Neutralizing antibody titers were lower in umbilical cord than maternal sera, although this finding did not achieve statistical significance (maternal sera, median, 104.7; interquartile range, 61.2-188.2; cord sera, median, 52.3; interquartile range, 11.7-69.6; P=.05). The second vaccine dose (boost dose) increased severe acute respiratory syndrome coronavirus 2-specific immunoglobulin G, but not immunoglobulin A, in maternal blood and breastmilk. No differences were noted in reactogenicity across the groups. CONCLUSION: Coronavirus disease 2019 messenger RNA vaccines generated robust humoral immunity in pregnant and lactating women, with immunogenicity and reactogenicity similar to that observed in nonpregnant women. Vaccine-induced immune responses were statistically significantly greater than the response to natural infection. Immune transfer to neonates occurred via placenta and breastmilk.

AI snapshot

Written from the paper’s full text.

TL;DR

COVID-19 mRNA vaccination produced robust humoral immunity in pregnant and lactating women comparable to nonpregnant women, and vaccine-induced antibody titers exceeded those from natural SARS-CoV-2 infection in pregnancy. Vaccine-generated antibodies were detected in all umbilical cord blood and breastmilk samples, with IgG but not IgA increasing after the boost.

Key findings

  • Among 131 vaccine recipients (84 pregnant, 31 lactating, 16 nonpregnant), vaccine-induced immune responses were equivalent in pregnant and lactating vs nonpregnant women; all titers were higher than those induced by SARS-CoV-2 infection during pregnancy (Kruskal-Wallis p<0.001).
  • Vaccine-generated antibodies were present in all umbilical cord blood samples (10/10) and breastmilk samples (N=31). IgG, but not IgA, increased in maternal blood and breastmilk with vaccine boost; breastmilk IgG1 RBD rose from 3.44 to 3.50 from V0 to V2 (p=0.002) but not V0 to V1 (3.44 to 3.45, p=0.7), with no significant rise in anti-RBD IgA or IgM after either dose.
  • Reactogenicity did not differ across groups. After the second dose, median (IQR) cumulative symptom scores were 2 (1-3), 3 (2-4), and 2.5 (1-4.5) in pregnant, lactating, and nonpregnant groups, respectively (p=0.40); fever/chills were reported by 32% (25/77) of pregnant women and 50% (8/16) of nonpregnant women (p=0.25).
  • The cord with the lowest Spike- and RBD-specific IgG belonged to a mother who delivered between the first and second vaccine doses, 17 days after dose 1, suggesting two doses may be essential to optimize humoral immune transfer to the neonate.

Methods

  • Prospective cohort study at two academic medical centers (December 17, 2020–February 23, 2021; samples obtained to March 2, 2021) enrolling 131 reproductive-age vaccine recipients: 84 pregnant, 31 lactating, and 16 nonpregnant women; comparison group was 37 pregnant women with natural SARS-CoV-2 infection 4–12 weeks prior.
  • Participant sera (N=131), umbilical cord sera (N=10), and breastmilk (N=31) were collected at baseline, second vaccine dose, 2–6 weeks post second dose, and delivery; SARS-CoV-2 Spike, RBD, S1, and S2 IgG, IgA, and IgM titers were quantified by multiplexed Luminex and confirmed by ELISA.
  • Post-vaccination symptoms were assessed with a cumulative symptom/reactogenicity score; analyses used Kruskal-Wallis tests, a repeated measures mixed effects model with correction for multiple comparisons, posthoc Tukey tests, Spearman correlations, and Wilcoxon matched-pairs signed rank tests, with significance at p<0.05.

Limitations

  • The paper states that these data do not elucidate potential risks to the fetus, that future studies in larger populations across gestational ages are needed, and that transfer kinetics across all pregnancy trimesters remain an important direction for future research.
  • The paper notes relatively few medical comorbidities in the pregnant group, limiting assessment of comorbidity associations.
  • Evident from the text: the cohort was small, especially for cord blood (N=10) and delivered participants (N=13); the population was primarily White, non-Hispanic women in their mid-30s reflecting the healthcare worker population at two hospitals, limiting generalizability; and the study was observational with no infant clinical outcomes reported.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.ajog.2021.03.023

Cites

32 of 32 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 19 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Composite symptom score after vaccination was significantly positively correlated with maternal serum Spike- and RBD-specific IgG1 and IgG3, breastmilk anti-Spike IgG1, IgG3 and IgA, and breastmilk anti-RBD IgG1.

    “Composite symptom score after vaccination was significantly positively correlated with maternal serum Spike-and RBD-specific IgG1 and IgG3, breastmilk anti-Spike IgG1, IgG3 and IgA, and breastmilk anti-RBD IgG1 (Table S2).”
    Quote in the paperSubstantial claim
  • Findingown data

    The cumulative symptom score after the first dose was low in all three groups.

    “The cumulative symptom score after the 1 st dose in all three groups was low.”
    Quote in the paperNot a substantial claim
  • Findingown data

    COVID-19 mRNA vaccination induced humoral immune responses in pregnant and lactating women that were equivalent to those in nonpregnant reproductive-age women.

    “Vaccine-induced immune responses were equivalent in pregnant and lactating vs nonpregnant women.”
    • Also stated in: § DISCUSSION · plain
      “robust and comparable IgG titers were observed across pregnant, lactating, and nonpregnant controls”
    Quote in the paperSubstantial claim
  • Findingown data

    Within pregnant women, medical comorbidities were not significantly associated with maternal serum antibody titers.

    “Within the pregnant women, medical comorbidities were not significantly associated with maternal serum antibody titers, although there were relatively few medical comorbidities in this group.”
    Quote in the paperNot a substantial claim
  • Findingown data

    Reactogenicity did not differ across pregnant, lactating, and nonpregnant COVID-19 mRNA vaccine recipients.

    “No differences were noted in reactogenicity across the groups.”
    • Also stated in: § Vaccination characteristics · plain
      “After the 2 nd dose, there was no significant difference between groups with respect to cumulative symptom score (median (IQR) 2 (1-3), 3 (2-4), and 2.5 (1-4.5) in pregnant, lactating, and nonpregnant groups respectively, p = 0.40).”
    • Also stated in: § DISCUSSION · plain
      “the side effect profile of pregnant women receiving the COVID-19 vaccines was not significantly different from non-pregnant women”
    Quote in the paperSubstantial claim
  • May combine two claims. 18
  • Classified as probably not a substantial claim. 9

  • May combine two claims.

    Findingown data

    Transfer of S-specific IgG1 into cord blood improved significantly with time from boost, but transfer of RBD-specific IgG1 did not.

    “Interestingly, there was a significant improvement of transfer of S-, but not RBD-, specific IgG1 into the cord with time from boost (Fig 2D/E), suggesting that time from vaccination may be an important determinant of transfer rates of specific IgG subpopulations following immunization in pregnancy (Supplemental Fig 4A/B).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    SARS-CoV-2-specific IgG, but not IgA, increased in maternal blood and breastmilk with the vaccine boost.

    “SARS-CoV-2 specific IgG, but not IgA, increased in maternal blood and breastmilk with vaccine boost.”
    • Also stated in: § Impact of maternal vaccination on breastmilk antibody transfer · plain
      “a boost in breastmilk IgG levels was observed (Fig 2A), concomitant with the boost observed systemically/in maternal serum (Fig 1A).”
    • Also stated in: § Impact of maternal vaccination on breastmilk antibody transfer · plain
      “IgA and IgM levels did not increase with boosting, in synchrony with a minimal boost in these isotypes in serum (Fig 1C/D and Supplemental Fig 1A-E).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    A significant rise in all antibody isotypes across all measured antigens occurred from baseline to first vaccine dose, with a further rise in IgG from first to second dose in pregnant and lactating women.

    “A significant rise in all isotypes across all antigens was observed from V0 to V1 , with a further rise in IgG levels from V1 to V2 in both the pregnant and lactating groups (Fig 1A-D and Supplemental Fig 1).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Composite reactogenicity score after the boost dose was significantly positively correlated with both maternal serum and breastmilk antibody titers.

    “Composite reactogenicity score after boost dose of vaccine was significantly positively correlated with both maternal serum and breastmilk antibody titers.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Injection site soreness, fatigue, and headache were the most common side effects after each vaccine dose, while fever/chills were also common after the second dose.

    “Injection site soreness, fatigue, and headache were the most common side effects after each vaccine dose, while fever/chills were also common after the 2 nd dose (Table 1).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    IgM and IgA responses were induced robustly after the prime dose and were poorly induced after boosting across all groups.

    “In contrast to IgG responses, IgM and IgA responses were induced robustly after the prime, and were poorly induced after boosting, across all groups (Fig 1C and D).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Spike-specific antibody titers rose more rapidly than RBD-specific titers after the first and second vaccine doses, but the magnitude of the response did not differ between pregnant and lactating women.

    “Spike titers rose more rapidly than RBDtiters after the first (V1/prime timepoint) and second (V2/boost timepoint) vaccine dose, but the magnitude of the response did not differ across pregnant or lactating women.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In breastmilk, anti-RBD IgG1 rose significantly from baseline to V2 but not from baseline to V1, and there was no significant rise in anti-RBD IgA or IgM after either dose.

    “IgG1 RBD rose significantly from V0 to V2 (3.44 to 3.50, p = 0.002) but not V0 to V1 (3.44 to 3.45, p=0.7) in breastmilk, and there was no significant rise in anti-RBD IgA or IgM in breastmilk after either dose (Supplemental Fig 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Vaccine-related fevers/chills were reported by 32% of pregnant women after the boost dose and 50% of nonpregnant women, with no significant difference (p=0.25).

    “Vaccine-related fevers/chills were reported by 32% (25/77) of pregnant women after the boost dose and 50% (8/16) of non-pregnant (p=0.25).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Both EUA-approved COVID-19 vaccines (Pfizer/BioNTech and Moderna) use mRNA to deliver the SARS-CoV-2 Spike antigen to the immune system.

    “both of which utilize mRNA to deliver SARS-CoV-2 Spike to educate the immune system 10,11”
    • Also stated in: § Vaccination characteristics · plain
      “Both vaccines use mRNA to deliver the SARS-CoV-2 Spike antigen to the immune system 10,11”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [10] Stafford, 2021, The coronavirus disease 2019 vaccine in pregnancy: risks, benefits, and recommendations, Am J Obstet Gynecol source

      Not checked in the free run.

    • cites [11] Zipursky, 2021, Pregnancy, breastfeeding and the SARS-CoV-2 vaccine: an ethics-based framework for shared decision-making, CMAJ source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    mRNA COVID-19 vaccines have shown highly effective immune induction in nonpregnant adults.

    “While mRNA vaccines have shown highly effective immune induction in non-pregnant adults, the immunogenicity and reactogenicity of this platform in pregnancy remains unclear.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [10] Stafford, 2021, The coronavirus disease 2019 vaccine in pregnancy: risks, benefits, and recommendations, Am J Obstet Gynecol source

      Not checked in the free run.

    • cites [11] Zipursky, 2021, Pregnancy, breastfeeding and the SARS-CoV-2 vaccine: an ethics-based framework for shared decision-making, CMAJ source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    IgG transfer through breastmilk increased significantly with boost, resulting in delivery of high levels of IgG to the neonate through breastmilk.

    “Additionally, while the transferred levels of IgA through breastmilk did not increase with boosting, IgG transfer increased significantly with boost, resulting in the delivery of high levels of IgG to the neonate through breastmilk.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    SARS-CoV-2 infection is more severe in pregnant women compared to nonpregnant counterparts, with increased risk of hospital admission, ICU stay, and death.

    “SARS-CoV-2 infection is more severe in pregnant women compared to their non-pregnant counterparts, with an increased risk of hospital admission, ICU stay, and death 2 .”
    • Also stated in: § DISCUSSION · plain
      “pregnancy is a risk factor for severe disease 27,28 .”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [2] Zambrano, 2020, Update: characteristics of symptomatic women of reproductive age with laboratory-confirmed SARS-CoV-2 infection by pregnancy status - United States, January 22-October 3, 2020, MMWR Morb Mortal Wkly Rep source

      Not checked in the free run.

    • cites [27] Ellington, 2020, Characteristics of women of reproductive age with laboratory-confirmed SARS-CoV-2 infection by pregnancy status - United States, January 22-June 7, 2020, MMWR Morb Mortal Wkly Rep source

      Not checked in the free run.

    • cites [28] Douedi, 2020, Novel coronavirus 2019 (COVID-19): a case report and review of treatments, Medicine (Baltimore) source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    Immune transfer to neonates occurred via placental and breastmilk routes after maternal COVID-19 mRNA vaccination.

    “Immune transfer to neonates occurred via placental and breastmilk.”
    • Also stated in: § DISCUSSION · plain
      “vaccine-induced IgG was transferred across the placenta to the fetus”
    • Also stated in: § DISCUSSION · plain
      “IgG transfer increased significantly with boost, resulting in the delivery of high levels of IgG to the neonate through breastmilk.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Higher IgA levels after the boost in pregnant Moderna recipients may be attributable to enhanced class switching following a longer boosting interval.

    “However, higher levels of IgA were noted after the boost in pregnant Moderna recipients, potentially attributable to enhanced class switching following a longer boosting interval.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    The study was a prospective cohort study at two academic medical centers.

    “131 reproductive-age vaccine recipients (84 pregnant, 31 lactating, and 16 nonpregnant) were enrolled in a prospective cohort study at two academic medical centers.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Febrile morbidity in pregnancy has been associated with congenital malformations when it occurs in the first trimester, and with adverse neurodevelopmental outcomes in offspring, although the level of risk remains controversial.

    “Febrile morbidity in pregnancy has been associated with congenital malformations 24 when it occurs in the first trimester, and adverse neurodevelopmental outcomes in offspring 25 , although the level of risk remains controversial 26 .”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [24] Graham, 1998, Teratogen update: gestational effects of maternal hyperthermia due to febrile illnesses and resultant patterns of defects in humans, Teratology source

      Not checked in the free run.

    • cites [25] Dreier, 2014, Systematic review and meta-analyses: fever in pregnancy and health impacts in the offspring, Pediatrics source

      Not checked in the free run.

    • cites [26] Sass, 2017, Fever in pregnancy and the risk of congenital malformations: a cohort study, BMC Pregnancy Childbirth source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation

    Antibody quantification was performed using a multiplexed Luminex assay as described previously and confirmed by ELISA.

    “Titers of SARS-CoV-2 Spike and RBD IgG, IgA and IgM were quantified in participant sera (N=131), umbilical cord sera (N=10), and breastmilk (N=31) at baseline, 2nd vaccine dose, 2-6 weeks post 2nd vaccine, and delivery by Luminex, and confirmed by ELISA.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [12] Sahin, 2020, COVID-19 vaccine BNT162b1 elicits human antibody and T H 1 T cell responses, Nature source

      Not checked in the free run.

    • cites [13] Jackson, 2020, An mRNA vaccine against SARS-CoV-2 - preliminary report, N Engl J Med source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The V2 timepoint reflects full antibody complement, achieved one week after Pfizer/BioNTech and two weeks after Moderna/NIH vaccination.

    “The V2 timepoint reflects full antibody complement, achieved one week after Pfizer/BioNTech and two weeks after Moderna/NIH 10,11 .”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [10] Stafford, 2021, The coronavirus disease 2019 vaccine in pregnancy: risks, benefits, and recommendations, Am J Obstet Gynecol source

      Not checked in the free run.

    • cites [11] Zipursky, 2021, Pregnancy, breastfeeding and the SARS-CoV-2 vaccine: an ethics-based framework for shared decision-making, CMAJ source

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductown data

    Statistical analyses used Kruskal-Wallis tests and a mixed effects model with correction for multiple comparisons.

    “Kruskal-Wallis tests and a mixed effects model, with correction for multiple comparisons, were used to assess differences between groups.”
    • Also stated in: § DISCUSSION · plain
      “Within and between group analyses of log10 transformed antibody levels in serum or breastmilk across multiple timepoints were evaluated by a repeated measures mixed effects (REML) model, followed by posthoc Tukey's multiple comparisons test.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Emerging data point to a critical role for breastmilk IgG in neonatal immunity against HIV, RSV, and influenza.

    “Importantly, emerging data point to a critical role for breastmilk IgG in neonatal immunity against several other vaccinatable viral pathogens including HIV, RSV, and influenza [19][20][21] .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [19][20][21]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    IgA dominates breastmilk profiles in natural SARS-CoV-2 infection.

    “In contrast, IgA dominates breastmilk profiles in natural SARS-CoV-2 infection 22 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [22] Pace, 2021, Characterization of SARS-CoV-2 RNA, antibodies, and neutralizing capacity in milk produced by women with COVID-19, mBio source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    The study was approved by an IRB (protocol #2020P003538).

    “Women at two tertiary care centers were approached for enrollment in an IRB-approved (protocol #2020P003538) COVID-19 pregnancy and lactation biorepository study between December 17, 2020 and February 23, 2021.”
    Quote in the paperNot a substantial claim
23 of 23

  • The paper relies on this without support.

    Pregnant and lactating women were excluded from initial COVID-19 vaccine trials.

    “Despite their higher risk, pregnant and lactating women were not included in any initial coronavirus disease 19 (COVID-19) vaccine trials, although the first vaccine trial began in pregnant women in February of 2021 (Pfizer/BioNTech, ClinicalTrials.govIdentifier: NCT04754594).”
    “pregnant women were not included in COVID-19 vaccine clinical trials”

  • The paper relies on this without support.

    The immunogenicity and reactogenicity of mRNA COVID-19 vaccines in pregnancy were unclear at the time of the study.

    “While mRNA vaccines have shown highly effective immune induction in non-pregnant adults, the immunogenicity and reactogenicity of this platform in pregnancy remains unclear.”
    “it remains unclear whether this novel vaccine approach will drive immunity in the context of pregnancy and location, and whether antibodies will be transferred efficiently to neonates via the cord and breastmilk.”

  • The paper relies on this without support.

    Whether antibodies would be transferred efficiently to neonates via cord and breastmilk was unclear.

    “whether antibodies will be transferred efficiently to neonates via the cord and breastmilk.”
    “However, whether these antibodies were transferred efficiently to infants remained unclear.”

  • The paper relies on this without support.

    Maternal IgG is capable of crossing the placenta to confer immunity to the neonate.

    “Maternal IgG is also capable of crossing the placenta to confer immunity to the neonate.”
4 of 4

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Functional neutralizing antibodies against SARS-CoV-2 were found in infant cord blood and in the breast milk of vaccinated pregnant women.

    “Importantly, functional neutralizing antibodies against SARS-CoV-2 were found in infant cord blood and in the breast milk of vaccinated pregnant women”

    From COVID-19 mRNA vaccines: Platforms and current developments (2022) · cites this paper as [116]

  • The presence of functional neutralizing antibodies in infant cord blood and breast milk suggests a protective effect for newborns.

    “suggesting that there is a protective effect for newborns.116, 117, 118”

    From COVID-19 mRNA vaccines: Platforms and current developments (2022) · cites this paper as [116]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

  • First-dose side-effect denominator does not match the stated missing data

    Minor

    The cohort included 84 pregnant participants, and the note says only one pregnant participant did not provide first-dose side-effect data. That would leave 83, not the stated denominator of 79.

    Reported 79 · recomputed 83

1 of 1

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Authors
Gray, K. J., Bordt, E. A., Atyeo, C., Deriso, E., Akinwunmi, B., Young, N., Baez, A. M., Shook, L. L., Cvrk, D., James, K., De Guzman, R., Brigida, S., Diouf, K., Goldfarb, I., Bebell, L. M., Yonker, L. M., Fasano, A., Rabi, S. A., Elovitz, M. A., Alter, G., & Edlow, A. G.
Affiliations
  • Brigham and Women's Hospital (US)
  • Harvard University (US)
  • Ragon Institute of MGH, MIT and Harvard (US)
  • University of Pennsylvania (US)
Corresponding author
  • Alter, Galit
  • Edlow, Andrea G.
ORCID
Venue
American Journal of Obstetrics and Gynecology
Publisher
Elsevier BV
Published
2021-09
Volume
225
Issue
3
Pages
303.e1-303.e17
ISSN
0002-9378 (ISSN-L)
DOI
10.1016/j.ajog.2021.03.023
PMC
PMC7987048
OpenAlex
W3145977403
Semantic Scholar
342eda6b6703d9ac696c81a568ad4a1124d4ca67
Cited by
699
References
32
Citations by year
2026: 23 · 2025: 35 · 2024: 76 · 2023: 137 · 2022: 229 · 2021: 197 · 2020: 1
FWCI
50.71
Type
journal article
Language
en
Open access
Licence
Locations
  • American Journal of Obstetrics and Gynecology (publishedVersion, cc-by)
  • medRxiv (acceptedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion)
  • Informationszentrum Lebenswissenschaften (ZB MED) (submittedVersion, cc-by)
  • ImmPort
Funders
  • Bill and Melinda Gates Foundation
  • Massachusetts General Hospital
  • Massachusetts Institute of Technology
  • National Institutes of Health
  • Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01HD100022)
  • National Heart, Lung, and Blood Institute (3K08HL146963-02S1)
  • National Institute of Allergy and Infectious Diseases (1U01CA260476-01, 3R37AI080289-11S1, R01A1145840, R01AI146785, U19AI135995-02, U19AI42790-01)
Topics
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Health Sciences › Medicine › Obstetrics and Gynecology › COVID-19 Impact on Reproduction
  • Social Sciences › Health › Vaccine Coverage and Hesitancy
Keywords
COVID-19 vaccines, SARS-CoV-2, pregnancy, lactation, mRNA vaccines, immunogenicity, reactogenicity, umbilical cord blood, maternal antibodies, neutralizing antibodies, vaccine safety in pregnancy

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