COVID-19 Vaccination and Preterm Birth: Current Evidence and Gaps Volume 60- Issue 3

Amália Cinthia Meneses do Rêgo¹ and Irami Araújo-Filho^1,2*

• ¹Institute of Teaching, Research, and Innovation, Liga Contra o Câncer, Full Professor of the Postgraduate Program in Biotechnology at Potiguar University, Potiguar University (UnP), Brazil
• ²Full Professor, Department of Surgery, Potiguar University. Ph.D. in Health Science, Brazil

Received: January 27, 2024; Published: February 06, 2025

*Corresponding author: Irami Araújo-Filho, Postgraduate Program in Biotechnology at Potiguar University/ UnP, Full Professor Department of Surgery, Federal University of Rio Grande do Norte. Full Professor, Department of Surgery, Potiguar University. Ph.D. in Health Science/ Natal-RN, Brazil

DOI: 10.26717/BJSTR.2025.60.009460

Abstract PDF

This review article examines current evidence on COVID-19 vaccination in pregnant women, focusing on its safety, efficacy, and impact on preventing infectious complications, particularly preterm birth. Numerous studies indicate that maternal vaccination is safe and effective in mitigating the risk of severe SARS-CoV-2-related infections, including a reduced incidence of premature deliveries. The vaccine’s immune response supports intrauterine stability, reducing disease-related inflammatory effects. Additionally, maternal vaccination facilitates antibody transfer to the fetus, potentially offering newborns protection in their initial months of life. While findings to date consistently highlight substantial benefits, several gaps remain. These include comparative analyses of different vaccine types, effects in high-risk pregnancies, and the longevity of immunity provided by booster doses. Further research is needed across diverse and vulnerable populations to broaden the global applicability of vaccination recommendations. This review supports the continued promotion of COVID-19 vaccination for pregnant women as a critical public health strategy. Effective communication strategies are essential to enhance vaccine uptake and reduce hesitancy. Expanding longitudinal studies on the effects of maternal vaccination will be pivotal for refining guidelines and supporting informed decision-making by healthcare providers and pregnant individuals.

Keywords: COVID-19; Vaccines; Pregnancy; Immunization; Sars-Cov-2; Pregnancy Complications; Premature Birth

The COVID-19 pandemic, triggered by SARS-CoV-2, has posed severe challenges worldwide, particularly affecting vulnerable populations such as pregnant women. Early in the pandemic, evidence highlighted the association between SARS-CoV-2 infection in pregnancy and an increased risk of significant obstetric complications, notably preterm birth [1-3]. This condition, defined as delivery before 37 weeks of gestation, remains a leading cause of neonatal morbidity and mortality globally. Preterm birth is associated with various health complications for newborns, including respiratory issues, neurological impairments, and weakened immune responses, often necessitating intensive medical care [4-6]. Identifying factors and interventions that can mitigate the risk of preterm birth among pregnant women affected by COVID-19 has, therefore, become a critical public health priority [5-7]. SARS-CoV-2 infection induces a robust inflammatory response within the body, which the altered immune function may further intensify during pregnancy. The immune system of pregnant women undergoes modifications that can make them more susceptible to viral infections and complicate the immune response [8-10]. Studies suggest that this pro-inflammatory state, combined with immunological changes intrinsic to pregnancy, may heighten the likelihood of adverse outcomes, including pre-term birth [11]. Consequently, there is an urgent need to establish targeted preventive measures to reduce the risks and complications associated with COVID-19 among pregnant populations.

Within this framework, COVID-19 vaccines have become essential in mitigating the adverse effects of the pandemic on maternal and neonatal health [12-14]. The widespread deployment of COVID-19 vaccines, such as mRNA and inactivated vaccines, has been pivotal in controlling viral transmission and reducing disease severity [15]. However, pregnant women were frequently excluded from early clinical trials, leading to ongoing questions regarding the safety and efficacy of these vaccines during pregnancy [16,17]. Preliminary studies indicate that COVID-19 vaccination is generally safe for pregnant women and, beyond reducing severe SARS-CoV-2 infection, may also decrease the incidence of adverse pregnancy outcomes, including preterm birth [18]. Despite these encouraging findings, the scientific literature still lacks robust, detailed data on the effectiveness of COVID-19 vaccination in preventing prematurity, particularly in different gestational subgroups with varying degrees of vulnerability [19-21]. One underexplored aspect in the literature is the effect of maternal vaccination on specific subgroups of preterm infants, such as highly preterm and moderately preterm infants. Each category of preterm birth presents distinct clinical characteristics and corresponding risks of neonatal complications [22-24]. More segmented research could elucidate which groups of preterm infants benefit most from maternal vaccination, supporting the development of more precise and individualized vaccination guidelines for pregnant women [25].

Furthermore, a subgroup-specific approach would deepen the understanding of the protective mechanisms provided by the vaccine concerning gestational development [26]. A further consideration is the diverse range of COVID-19 vaccines available globally, particularly mRNA and inactivated vaccines, and the different dosing schedules used [27]. While mRNA vaccines are widely utilized and have demonstrated a favorable safety profile in pregnant women, inactivated vaccines remain an essential option, especially in developing countries [28,29]. Direct comparisons between these vaccine types are scarce, making it difficult to determine which type or dosing regimen may provide the optimal balance of efficacy and safety for preventing preterm birth [30]. Investigating these variables is crucial to inform public health policies across various epidemiological settings, especially in regions where logistical and economic factors limit vaccine choice [31-33]. The long-term impact of COVID-19 vaccination on preterm infants exposed in utero represents an emerging area of interest. Initial studies primarily examine immediate neonatal outcomes, such as birth weight and respiratory support requirements. However, limited information regarding these children’s neurocognitive and immunological development over their early years is available [34-36]. The lack of longitudinal studies tracking the development of preterm neonates exposed to maternal vaccination highlights a significant scientific gap, as specific effects-whether adverse or beneficial- may only manifest over extended follow-up periods.

Therefore, research focusing on these long-term outcomes is essential to provide a more comprehensive view of the implications of vaccination during pregnancy [37-39]. It is vital to assess the efficacy of COVID-19 vaccination in pregnant women who have conditions that elevate the risk of preterm birth, such as gestational hypertension and diabetes. These pre-existing conditions markedly increase the likelihood of obstetric complications, and vaccination may offer additional protection for these women [40-42]. The current literature provides limited insights into COVID-19 vaccination in pregnant women with such conditions, hindering the development of tailored guidelines for this subgroup. Further studies could yield valuable data to support personalized clinical decision-making and improve obstetric and neonatal outcomes [43-45]. Understanding the immunological mechanisms by which maternal vaccination might reduce the risk of preterm birth is another developing area of research. The immune response induced by immunization could create a more stable intrauterine environment, helping protect the fetus and reduce the likelihood of premature delivery [33,46]. Nonetheless, the exact pathways through which maternal immunization confers this protection remain largely unknown. Investigating these biological mechanisms is critical for understanding how vaccination prevents pregnancy complications, thus establishing a sound scientific basis for these interventions [14,47].

The emergence of new SARS-CoV-2 variants, such as Delta and Omicron, has introduced additional concerns about the effectiveness of COVID-19 vaccination in preventing preterm births across diverse epidemiological contexts. Each viral variant possesses unique transmission and virulence characteristics, which may alter the immune response among vaccinated pregnant women [29,48]. Evaluating vaccine effectiveness against these variants is essential to ensure continued protection for pregnant women and their infants as the virus evolves. Adapting vaccination strategies based on prevalent variants is fundamental to sustained maternal and neonatal health protection [41,49]. Most studies on COVID-19 vaccination and preterm birth have been conducted in developed countries, where access to high-quality healthcare is more readily available. This geographical focus restricts the applicability of findings globally, particularly for populations in developing countries where socioeconomic constraints and healthcare access limitations can affect immune response and obstetric outcomes [22,50]. Conducting representative studies that include diverse ethnic and geographic populations is crucial to validate findings and broaden the applicability of data globally, ensuring that evidence on COVID-19 vaccination and prematurity is relevant for various demographics [8-10]. Vaccine hesitancy among pregnant women, driven by concerns about vaccine safety and potential effects on the fetus, remains a substantial barrier to achieving optimal vaccination rates.

The literature indicates several factors influence vaccination acceptance during pregnancy, including reliable information and access to trusted medical guidance [46,51]. Pregnant women’s perceptions and barriers regarding vaccination is vital for designing communication strategies that promote adherence. Informed approaches that address these concerns can foster greater confidence in vaccination, ultimately enhancing maternal and neonatal health outcomes [30]. Vaccination during pregnancy is a relatively new preventive strategy, and its safety and efficacy continue to be explored from multiple perspectives and in diverse settings. Ongoing monitoring of obstetric and neonatal outcomes associated with maternal vaccination is critical, as additional evidence may support or refine existing guidelines [43,47]. With continuous data collection and analysis, a more robust foundation for public health policy can be established, enabling healthcare providers and pregnant women to make informed decisions about the benefits and potential risks of COVID-19 vaccination during pregnancy [8,24]. Another emerging issue is the administration of COVID-19 vaccine booster doses in pregnant women. Initial findings suggest that booster doses may be safe and effective, but whether specific gestational subgroups might respond differently to this regimen remains unclear. Monitoring pregnant women who receive booster doses is necessary to ensure this practice is safe and beneficial, especially for those with additional obstetric risk factors [40,52].

Despite encouraging data on the benefits of COVID-19 vaccination in pregnancy, numerous questions remain unanswered. Continued research targeting the identified scientific gaps, including vaccine type, maternal health conditions, and viral variants, is essential for a more comprehensive understanding of COVID-19 vaccination effects in pregnant populations. As new findings emerge, more specific and tailored guidelines can be developed to protect maternal and child health amid the pandemic [38,45]. In this sense, this review seeks to critically examine the current scientific evidence on the impact of COVID-19 vaccination on preterm birth, highlighting both advancements and remaining data gaps. By synthesizing existing knowledge and identifying critical areas for future research, this review aims to provide a solid foundation for public health policy formulation and guide ongoing investigations on maternal vaccination, ultimately enhancing understanding of how COVID-19 immunization during pregnancy affects neonatal and maternal health outcomes [14-16].

This review study was designed to assess the effectiveness of COVID-19 vaccination among pregnant women and its role in mitigating infectious complications during pregnancy, with a particular emphasis on prematurity-related outcomes. A systematic literature search was conducted across multiple scientific databases, including PubMed, Scopus, Embase, Web of Science, SciELO, and Google Scholar, the latter being utilized as a source of gray literature. This search encompassed all data available up to the present time. The search strategy was constructed using specific keywords and terms such as “COVID-19,” “Vaccines,” “Pregnancy,” “Immunization,” “SARS-CoV-2,” “Pregnancy Complications, Infectious,” and “Premature Birth.” Boolean operators (AND, OR) were applied to refine search results and ensure the comprehensive retrieval of studies relevant to this topic. Inclusion criteria for this review span a range of study designs, including randomized clinical trials, cohort studies, case-control studies, cross-sectional studies, case series, systematic reviews, and meta-analyses. Studies were selected based on their comparative analysis of vaccinated versus unvaccinated pregnant women, focusing on clinical outcomes such as prematurity, the safety profile of immunization, the efficacy of preventing infectious complications, and potential long-term health implications for neonates. Two reviewers who screened titles and abstracts independently performed the study selection process to maintain an unbiased and thorough review.

In instances where discrepancies arose between reviewers, resolution was sought through discussion; if necessary, a third reviewer provided arbitration. To further minimize bias, reviewers were blinded to the identities of the study authors and their institutional affiliations during the selection process. Data extraction was conducted following a standardized protocol, with key data points collected on study design, population demographics, primary findings, and outcomes related to COVID-19 vaccination during pregnancy. Thematic analysis was employed to categorize the findings into core themes. Major themes included the efficacy of COVID-19 vaccination in preventing infectious complications during pregnancy, its influence on preterm birth rates, and the safety for both mother and fetus, as well as the implications for neonatal health in the long term. Additionally, the analysis addressed vaccine accessibility, particularly in low- and middle-income settings, and discussed the prospective benefits of maternal immunization for the newborn’s health. This review provides a comprehensive synthesis of current literature, offering insights into the strengths and limitations of COVID-19 vaccination for pregnant women. By identifying existing knowledge gaps and proposing avenues for future research, this review seeks to contribute to a broader understanding of how maternal vaccination strategies can be optimized to ensure the highest levels of protection for both mother and child across diverse healthcare environments.

The connection between COVID-19 vaccination and decreased risk of preterm birth has become a prominent area of obstetric research since the pandemic began. A growing body of evidence suggests that SARS-CoV-2 infection during pregnancy heightens the risk of various obstetric complications, particularly preterm birth (Table 1) [53,54]. The inflammatory response triggered by infection disrupts the intrauterine environment, increasing the chances of premature delivery and the subsequent health challenges prematurity entails [27]. This finding spurred researchers to investigate whether maternal COVID-19 vaccination could be a protective factor, potentially stabilizing the intrauterine environment and shielding both mother and fetus from adverse outcomes. Thus, understanding the complex benefits and limitations of COVID-19 vaccination for pregnant populations has become crucial in shaping public health strategies to promote maternal and neonatal health [55,56]. mRNA vaccines, such as Pfizer-BioNTech and Moderna, are widely recommended for pregnant women due to their well-documented safety profiles and effectiveness in reducing the severity of COVID-19. However, few studies have directly compared mRNA vaccines with inactivated vaccines, such as CoronaVac, specifically concerning preterm birth prevention [57]. This lack of comparative data limits our understanding of whether a particular vaccine type could offer more robust protection against prematurity.

Table 1: COVID-19 Vaccination - Pregnancy and Prematurity.

Note: Source: Authors.

While mRNA vaccines have demonstrated a strong immune response, the role of inactivated vaccines remains significant, especially in regions where these vaccines are more accessible. Determining if there are substantial differences between vaccine types is essential to guide recommendations in settings where vaccine choice is constrained by supply or policy [58,59]. Beyond vaccine type, the dosing regimen is also critically important in developing effective maternal immunization strategies. Early data suggest that the number of doses a pregnant woman receives could influence her immune response and, subsequently, the level of fetal protection [30,41]. Research indicates that booster doses might offer an additional defense against infection-related inflammatory responses, promoting immune homeostasis within the uterus and reducing the risk of preterm birth [60]. However, further research is needed to elucidate the effects of booster doses and their timing, especially in high-transmission areas, to assess if they confer additional benefits to maternal and fetal health across varied epidemiological contexts [61]. Although immediate neonatal outcomes such as birth weight and respiratory needs are commonly studied, the long-term effects of maternal vaccination on children’s health are less understood [34]. Longitudinal studies tracking infants through early childhood would be invaluable for understanding the implications of maternal immunization on neurocognitive development and immune system maturation [62].

This research is critical, as it may reveal whether vaccination during pregnancy supports neonatal immune resilience over time or if any atypical responses could arise later in life. The findings from such studies would be instrumental in shaping maternal vaccination programs and public health policies aimed at fostering long-term health in mothers and infants [62,63]. Prolonged follow-up on vaccinated neonates could also elucidate whether maternal vaccination confers indirect protection against infections in early infancy-a period when immune defenses are still developing [64]. Preliminary evidence suggests that maternal antibodies transferred through the placenta could protect newborns against SARS-CoV-2 and possibly other pathogens in the early months of life [65]. If confirmed, this protective effect would reinforce the value of maternal immunization. Additionally, assessing broader health outcomes, such as neurological and immune- related metrics, would provide a comprehensive view of maternal vaccination’s long-term impact on child health [66]. Pregnant women with high-risk conditions, such as gestational hypertension or diabetes, represent a particularly vulnerable subgroup for whom COVID-19 vaccination may offer yet unexplored protective benefits [55,60]. These preexisting conditions are strongly linked to increased prematurity risk, and vaccination could provide an additional safeguard, potentially reducing infection-related complications [67].

The literature on vaccine efficacy within these high-risk subgroups remains limited, complicating the creation of targeted guidelines. Future studies should prioritize including high-risk pregnant populations to determine whether immunization strategies should be tailored to enhance protection in those with obstetric risk factors [68,69]. Another crucial factor is the timing of vaccination during pregnancy. Research into immune response variations across trimesters could remarkably inform optimal vaccination schedules, as studies suggest that placental antibody transfer rates and vaccine efficacy may fluctuate depending on the stage of pregnancy [70]. Understanding how timing affects fetal immunity is especially relevant for optimizing vaccination protocols and could yield insights that refine current maternal vaccination guidelines [71]. COVID-19 vaccines’ impact on placental function and development is a vital yet underexplored area. The placenta is essential for nutrient transfer and fetal protection, and understanding whether vaccines influence placental health, including vascular function and immune interactions, could reveal new dimensions of fetal safety and development [38,72]. While vaccines generally appear safe, data on possible effects on placental biology would enhance our understanding of how vaccines might impact fetal growth and birth timing and clarify any potential risks or benefits related to placental adaptation during pregnancy [40].

Comparing COVID-19 vaccination with other established maternal vaccines, such as influenza and Tdap, may provide a valuable framework for assessing COVID-19 vaccines’ benefits and risks [26]. Both influenza and Tdap vaccines have demonstrated efficacy in preventing respiratory diseases and neonatal infections during pregnancy, highlighting the importance of maternal immunization against infectious agents. By drawing parallels, researchers can better understand if COVID-19 vaccines similarly offer protective effects, especially in high-transmission settings, or if they confer unique benefits or risks compared to traditional maternal vaccines [73-75]. The emergence of SARS-CoV-2 variants, such as Delta and Omicron, poses additional challenges to maternal vaccination programs. Each variant’s unique properties regarding transmissibility and virulence could affect vaccine effectiveness, especially in pregnant populations [6-8]. Evidence indicates that the immune response in vaccinated pregnant women might vary depending on the circulating variant, emphasizing the need for ongoing efficacy assessments as new strains arise [60]. Studies on the effectiveness of different vaccine formulations and dosing strategies against these variants will be crucial in adapting vaccination protocols to ensure consistent protection for pregnant women and their infants [76]. Vaccine hesitancy among pregnant women remains a significant barrier to achieving widespread immunization.

Concerns regarding vaccine safety and fetal effects contribute to this hesitancy, often compounded by the lack of accessible, evidence- based information. Addressing these concerns requires targeted public health initiatives that deliver clear, accurate information about the benefits of maternal vaccination [77,78]. Effective communication strategies focusing on vaccination’s safety, efficacy, and broader public health impacts can play a crucial role in fostering trust among pregnant women, ultimately increasing vaccination rates and improving maternal and neonatal health outcomes [79]. Healthcare access disparities also complicate maternal vaccination efforts globally. Many studies on vaccination and prematurity are conducted in developed nations with high healthcare quality and availability. However, these findings may not translate directly to developing regions, where healthcare disparities and socioeconomic factors influence immune responses and pregnancy outcomes [67,80]. Future research must include diverse populations from the underrepresented areas to achieve global maternal and neonatal health equity. This inclusivity will help validate findings across various settings, ensuring that vaccination guidelines meet the needs of all populations [81]. To fully realize the global benefits of maternal vaccination, studies must include populations from diverse socioeconomic backgrounds and ethnicities.

Research in underserved regions and among varied demographics is necessary to strengthen the global evidence base, ensuring that vaccination policies are equitable and applicable to diverse populations [82,83]. A more inclusive approach will offer critical insights into how ethnicity, geographical factors, and healthcare access influence vaccine efficacy and safety, ultimately contributing to tailored, culturally relevant guidelines [75,79]. Another emerging topic is the potential benefit of booster doses for pregnant women. Preliminary studies suggest that boosters may enhance immunity, especially in high-exposure environments, yet additional research is needed to confirm their safety and efficacy across gestational stages [47]. Tracking outcomes for women who receive boosters will be essential, especially for those with heightened obstetric risks, as this could reveal whether boosters significantly improve maternal and neonatal outcomes [80]. Although data on COVID-19 vaccination in pregnancy are promising, many questions remain. Research addressing critical gaps—such as optimal vaccine types, ideal dose schedules, interactions with maternal health conditions, and immune responses to emerging variants—will be instrumental in refining clinical recommendations. Answering these questions will help create evidence-based vaccination strategies that protect pregnant women and their infants in various settings [81-83]. Examining COVID-19 vaccination’s impact on neonatal outcomes beyond prematurity could further inform vaccination policies [84].

For instance, studies exploring rates of congenital infections, respiratory distress, and NICU admissions among vaccinated mothers’ infants could add depth to our understanding of maternal vaccination benefits. This broader health assessment could reveal additional neonatal benefits and contribute to more comprehensive maternal health guidelines [85,86]. Long-term studies on preterm infants exposed to COVID-19 vaccination in utero, particularly regarding neurocognitive and immune development, are critical for assessing the vaccine’s extended impacts [87]. Follow-up research tracking these infants through early childhood would provide invaluable insights into how maternal vaccination influences immune resilience and neurodevelopment, shedding light on the broader benefits and risks associated with prenatal vaccine exposure [88]. COVID-19 vaccination in pregnant women represents a vital intervention to mitigate risks associated with SARS-CoV-2 infection, including preterm birth and other adverse outcomes [84]. However, a more in-depth exploration of critical questions-such as differences between vaccine types, dose timing, maternal immune responses across viral variants, and specific benefits for high-risk groups-is necessary to maximize the protective potential of maternal vaccination [89]. Expanding longitudinal studies, increasing population diversity, and refining analysis by gestational age are essential to ensure maternal vaccination guidelines offer global comprehensive, equitable, and individualized protection for maternal and neonatal health [90].

This review underscores the critical role of COVID-19 vaccination in pregnancy as a protective measure for maternal and neonatal health. Evidence increasingly supports that maternal vaccination is safe and effective in mitigating severe infectious complications during pregnancy, notably reducing the risk of preterm birth. The immunological response triggered by the vaccine appears to promote a more stable intrauterine environment, reducing inflammation associated with SARS-CoV-2 infection. Furthermore, vaccination facilitates maternal antibody transfer, potentially offering early immunological support to newborns during their initial months. Despite consistent findings on the benefits and safety of COVID-19 vaccination for pregnant women, further research is needed to address the remaining gaps. Areas for future study include comparative efficacy among different vaccine types, outcomes in high-risk pregnancies, and the impact of booster doses on the duration and breadth of immune protection. Additionally, further investigation into varied and underserved populations could enhance the global relevance of vaccination guidelines. Current evidence supports continuing COVID-19 vaccination campaigns targeting pregnant women as a vital public health strategy. Efforts should focus on effective communication strategies to build trust and reduce vaccine hesitancy to maximize coverage.

Expanding longitudinal research on vaccination during pregnancy will be instrumental in refining recommendations, allowing healthcare providers and pregnant individuals to make well-informed, safe decisions.

The authors thank the Federal University of Rio Grande do Norte, Potiguar University, and Liga Contra o Cancer for supporting this study.

The authors declare that there is no conflict of interest.

1. Blakeway H, Prasad S, Kalafat E, Heath PT, Ladhani SN, et al. (2022) COVID-19 vaccination during pregnancy: coverage and safety. Am J Obstet Gynecol 226(2): 236.e1-236.e14.
2. Carbone L, Trinchillo MG, Di Girolamo R, Raffone A, Saccone G, et al. (2022) COVID-19 vaccine and pregnancy outcomes: A systematic review and meta-analysis. Int J Gynaecol Obstet 159(3): 651-661.
3. Jamieson DJ, Rasmussen SA (2022) An update on COVID-19 and pregnancy. Am J Obstet Gynecol 226(2): 177-186.
4. Male V (2022) SARS-CoV-2 infection and COVID-19 vaccination in pregnancy. Nat Rev Immunol 22(5): 277-282.
5. Rahmati M, Yon DK, Lee SW, Butler L, Koyanagi A, et al. (2023) Effects of COVID-19 vaccination during pregnancy on SARS-CoV-2 infection and maternal and neonatal outcomes: A systematic review and meta-analysis. Rev Med Virol 33(3): e2434.
6. Vesco KK, Denoble AE, Lipkind HS, Kharbanda EO, DeSilva MB, et al. (2024) Obstetric complications and birth outcomes after antenatal COVID-19 vaccination. Obstet Gynecol 143(6): 794-802.
7. Kalafat E, Heath P, Prasad S, O'Brien P, Khalil A (2022) COVID-19 vaccination in pregnancy. Am J Obstet Gynecol 227(2): 136-147.
8. Facciolà A, Micali C, Visalli G, Venanzi Rullo E, Russotto Y, et al. (2022) COVID-19 and pregnancy: clinical outcomes and scientific evidence about vaccination. Eur Rev Med Pharmacol Sci. 26(7): 2610-2626.
9. Du T, Qu Q, Zhang Y, Huang Q (2023) No observable influence of COVID-19 inactivated vaccines on pregnancy and birth outcomes in the first trimester of gestation. Expert Rev Vaccines 22(1): 900-905.
10. Barros FC, Gunier RB, Rego A, Sentilhes L, Rauch S, et al. (2024) Maternal vaccination against COVID-19 and neonatal outcomes during Omicron: INTERCOVID-2022 study. Am J Obstet Gynecol 231(4): 460.e1-460.e17.
11. Zhao Y, Zhao Y, Su X, Zhou Y, Zhang Z, et al. (2023) No association of vaccination with inactivated COVID-19 vaccines before conception with pregnancy complications and adverse birth outcomes: a cohort study of 5457 Chinese pregnant women J Med Virol 95(4).
12. Lipkind HS, Vazquez Benitez G, DeSilva M, Vesco KK, Ackerman Banks C, et al. (2022) Receipt of COVID-19 vaccine during pregnancy and preterm or small-for-gestational-age at birth - Eight integrated health care organizations, United States, December 15, 2020-July 22, 2021. MMWR Morb Mortal Wkly Rep 71(1): 26-30.
13. Shafiee A, Kohandel Gargari O, Teymouri Athar MM, Fathi H, Ghaemi M, et al. (2023) COVID-19 vaccination during pregnancy: a systematic review and meta-analysis. BMC Pregnancy Childbirth 23(1): 45.
14. Kachikis A, Pike M, Eckert LO, Roberts E, Frank Y, et al. (2024) Timing of maternal COVID-19 vaccine and antibody concentrations in infants born preterm. JAMA Netw Open 7(1).
15. Jaswa EG, Cedars MI, Lindquist KJ, Bishop SL, Kim YS, et al. (2024) In utero exposure to maternal COVID-19 vaccination and offspring neurodevelopment at 12 and 18 months. JAMA Pediatr 178(3): 258-265.
16. Hui L, Marzan MB, Rolnik DL, Potenza S, Pritchard N, et al. (2023) Reductions in stillbirths and preterm birth in COVID-19-vaccinated women: a multicenter cohort study of vaccination uptake and perinatal outcomes. Am J Obstet Gynecol 228(5): 585.e1-585.e16.
17. Torche F, Nobles J (2023) Vaccination, immunity, and the changing impact of COVID-19 on infant health. Proc Natl Acad Sci U S A 120(49).
18. Darwin KC, Kohn JR, Shippey E, Uribe KA, Gaur P, et al. (2023) Reduction in preterm birth among COVID-19-vaccinated pregnant individuals in the United States. Am J Obstet Gynecol MFM 5(10): 101114.
19. Kuriloff M, Patel E, Mueller A, Dada T, Duncan C, et al. (2023) COVID-19 and obstetric outcomes: a single-center retrospective experience in a predominantly Black population. J Matern Fetal Neonatal Med 36(1): 2196364.
20. Zhang D, Huang T, Chen Z, Zhang L, Gao Q, et al. (2023) Systematic review and meta-analysis of neonatal outcomes of COVID-19 vaccination in pregnancy. Pediatr Res 94(1): 34-42.
21. Grimes LP, Gerber JS (2024) Neonatal and infant infection with SARS-CoV-2. Semin Perinatol 48(4): 151922.
22. Piekos SN, Hwang YM, Roper RT, Sorensen T, Price ND, et al. (2023) Effect of COVID-19 vaccination and booster on maternal-fetal outcomes: a retrospective cohort study. Lancet Digit Health 5(9): e594-e606.
23. Fell DB, Dimanlig Cruz S, Regan AK, Håberg SE, Gravel CA, et al. (2022) Risk of preterm birth, small for gestational age at birth, and stillbirth after COVID-19 vaccination during pregnancy: population-based retrospective cohort study. BMJ 378: e071416.
24. Goldshtein I, Steinberg DM, Kuint J, Chodick G, Segal Y, et al. (2022) Association of BNT162b2 COVID-19 vaccination during pregnancy with neonatal and early infant outcomes. JAMA Pediatr 176(5): 470-477.
25. Ghesquiere L, Boivin G, Demuth B, Giguere Y, Forest JC, et al. (2024) Impact of COVID-19 and vaccination during pregnancy on placenta-mediated complications (COVIGRO study). J Obstet Gynaecol Can 46(4): 102291.
26. Maguire S, Al Emadi S, Alba P, Aguiar MC, Al Lawati T, et al. (2023) Obstetric outcomes in women with rheumatic disease and COVID-19 in the context of vaccination status. Rheumatology (Oxford) 62(4): 1621-1626.
27. Ha L, Levian C, Greene N, Goldfarb I, Hirsch A, et al. (2023) Association between acceptance of routine pregnancy vaccinations and COVID-19 vaccine uptake in pregnant patients. J Infect 87(6): 551-555.
28. Wang J, Deng Y, Wang W (2024) COVID-19 vaccination during pregnancy and adverse perinatal outcomes: a systematic review and meta-analysis. Trans R Soc Trop Med Hyg 118(7): 405-425.
29. Parums DV (2021) Editorial: Maternal SARS-CoV-2 infection and pregnancy outcomes from current global study data. Med Sci Monit 27: e933831.
30. Prasad S, Kalafat E, Blakeway H, Townsend R, O'Brien P, et al. (2022) Systematic review and meta-analysis of the effectiveness and perinatal outcomes of COVID-19 vaccination in pregnancy. Nat Commun 13(1): 2414.
31. Ding C, Liu Y, Pang W, Zhang D, Wang K, et al. (2023) Associations of COVID-19 vaccination during pregnancy with adverse neonatal and maternal outcomes: a systematic review and meta-analysis. Front Public Health 11: 1044031.
32. Theiler RN, Wick M, Mehta R, Weaver AL, Virk A, et al. (2021) Pregnancy and birth outcomes after SARS-CoV-2 vaccination in pregnancy. Am J Obstet Gynecol MFM 3(6): 100467.
33. Champigneulle O, Bennett CL (2022) Moderna, Pfizer-BioNTech, and Johnson & Johnson/Janssen post-COVID vaccine hematological adverse events including cerebral venous sinus thrombosis (CVST), thrombotic thrombocytopenia (VITT), blood clots, increased vaginal/menstrual bleeding and/or miscarriage, stillbirth delivery, or premature birth. Cancer Treat Res 184: 151-160.
34. Bleicher I, Kadour Peero E, Sagi Dain L, Sagi S (2021) Early exploration of COVID-19 vaccination safety and effectiveness during pregnancy: interim descriptive data from a prospective observational study. Vaccine 39(44): 6535-6538.
35. Licata F, Pelullo CP, Della Polla G, Citrino EA, Bianco A (2023) Immunization during pregnancy: do healthcare workers recommend vaccination against influenza? Front Public Health 11: 1171142.
36. Hui L, Marzan MB, Potenza S, Rolnik DL, Said JM, et al. (2021) Collaborative maternity and newborn dashboard (CoMaND) for the COVID-19 pandemic: a protocol for timely, adaptive monitoring of perinatal outcomes in Melbourne, Australia. BMJ Open 11(11).
37. Shimabukuro TT, Kim SY, Myers TR, Moro PL, Oduyebo T, et al. (2021) Preliminary findings of mRNA COVID-19 vaccine safety in pregnant persons. N Engl J Med 384(24): 2273-2282.
38. Tavares Veras Florentino P, Cerqueira Silva T, Freire De Carvalho L, Jôse Oliveira Alves F, De Araújo Oliveira V, et al. (2023) Safety of BNT162b2 and CoronaVac during pregnancy on birth outcomes and neonatal mortality: a cohort study from Brazil. Int J Epidemiol 52(6): 1708-1715.
39. Magnus MC, Örtqvist AK, Dahlqwist E, Ljung R, Skår F, et al. (2022) Association of SARS-CoV-2 vaccination during pregnancy with pregnancy outcomes. JAMA 327(15): 1469-1477.
40. Hatami D, Habibelahi A, Changizi N, Heidarzadeh M, Nojomi M, et al. (2024) Perinatal outcomes and Sinopharm BBIBP-CorV vaccination during pregnancy. BMC Pregnancy Childbirth 24(1): 190.
41. Dick A, Rosenbloom JI, Karavani G, Gutman Ido E, Lessans N, et al. (2022) Safety of third SARS-CoV-2 vaccine (booster dose) during pregnancy. Am J Obstet Gynecol MFM 4(4): 100637.
42. Meghani M, Razzaghi H, Kahn KE, Hung MC, Srivastav A, et al. (2023) Surveillance systems for monitoring vaccination coverage with vaccines recommended for pregnant women, United States. J Womens Health (Larchmt) 32(3): 260-270.
43. Wang D, Ning JD, Cao J, Liu C, Tang S, et al. (2024) The effect of COVID-19 vaccination on symptomatic infection and related symptoms among preterm-born children aged 3-7 years in China. Sci Rep 14(1): 25384.
44. Hui PW, Yeung LM, Ko JKY, Lai THT, Chan DMK, et al. (2024) COVID-19 vaccination and transmission patterns among pregnant and postnatal women during the fifth wave of COVID-19 in a tertiary hospital in Hong Kong. Hong Kong Med J 30(1): 16-24.
45. Lu L, Wang L, Feng T, Du X (2023) Safety evaluation of COVID-19 vaccination during early pregnancy: A single-center prospective cohort study of Chinese pregnant women. Hum Vaccin Immunother 19(2): 2226995.
46. Vidal MJ, Martínez Solanas È, Mendoza S, Sala N, Jané M, et al. (2023) Impact of SARS-CoV-2 infection in pregnant women and their babies: clinical and epidemiological features. Gac Sanit 37:102332.
47. Piekos SN, Hwang YM, Roper RT, Sorensen T, Price ND, et al. (2023) The effect of COVID-19 vaccination and booster on maternal-fetal outcomes: a retrospective multicenter cohort study. Lancet Digit Health 5(9): e594-e606.
48. Sanusi AA, Leach J, Boggess K, Dugoff L, Sibai B, et al. (2024) Pregnancy outcomes of nifedipine compared with labetalol for oral treatment of mild chronic hypertension. Obstet Gynecol 144(1): 126-134.
49. Akgül F, Tüzer C, Arslan Y, Sevim B (2023) COVID-19 infection during pregnancy: A retrospective study in a city in the Southeastern region of Turkey. Saudi Med J 44(3): 268-276.
50. Chen Z, Mu X, Wang X, Zhang L, Liu G, et al. (2023) Association of maternal inactivated COVID-19 vaccination within 3 months before conception with neonatal outcomes. Vaccines (Basel) 11(11): 1710.
51. Watanabe A, Yasuhara J, Iwagami M, Miyamoto Y, Yamada Y, et al. (2022) Peripartum outcomes associated with COVID-19 vaccination during pregnancy: a systematic review and meta-analysis. JAMA Pediatr 176(11): 1098-1106.
52. Yang C, Zheng Z, Zheng P, Chen J, Huang Q, et al. (2023) Inactivated COVID-19 vaccines in the peri-pregnancy period: evaluation of safety for both pregnant women and neonates. Vaccine 41(49): 7450-7459.
53. Bookstein Peretz S, Regev N, Novick L, Nachshol M, Goffer E, et al. (2021) Short-term outcome of pregnant women vaccinated with BNT162b2 mRNA COVID-19 vaccine. Ultrasound Obstet Gynecol 58(3): 450-456.
54. Uta M, Craina M, Marc F, Enatescu I (2024) Assessing the impact of COVID-19 vaccination on preterm birth: a systematic review with meta-analysis. Vaccines (Basel) 12(1): 102.
55. Meghani M, Razzaghi H, Pingali C, Crane B, Naleway A, et al. (2021) COVID-19 vaccination coverage among pregnant women during pregnancy - Eight integrated health care organizations, United States, December 14, 2020-May 8, 2021. MMWR Morb Mortal Wkly Rep 70(24): 895-899.
56. Du T, Qu Q, Zhang Y, Huang Q (2023) No observable influence of COVID-19 inactivated vaccines on pregnancy and birth outcomes in the first trimester of gestation. Expert Rev Vaccines 22(1): 900-905.
57. Wang D, Ning JD, Cao J, Liu C, Tang S, et al. (2024) The effect of COVID-19 vaccination on symptomatic infection and related symptoms among preterm-born children aged 3-7 years in China. Sci Rep 14(1):25384.
58. Grobman WA, Sandoval GJ, Metz TD, Manuck TA, Clifton RG, et al. (2023) The temporal relationship between the COVID-19 pandemic and preterm birth. Obstet Gynecol 141(6): 1171-1180.
59. Maguire S, Al Emadi S, Alba P, Aguiar MC, Al Lawati T, et al. (2023) Obstetric outcomes in women with rheumatic disease and COVID-19 in the context of vaccination status. Rheumatology (Oxford) 62(4):1621-1626.
60. Stock SJ, Moore E, Calvert C, Carruthers J, Denny C, et al. (2022) Pregnancy outcomes after SARS-CoV-2 infection in periods dominated by delta and omicron variants in Scotland: a population-based cohort study. Lancet Respir Med 10(12): 1129-1136.
61. Lu L, Wang L, Feng T, Du X (2023) Safety evaluation of COVID-19 vaccination during early pregnancy: A single-center prospective cohort study of Chinese pregnant women. Hum Vaccin Immunother 19(2): 2226995.
62. Prasad S, Kalafat E, Blakeway H, Townsend R, O'Brien P, et al. (2022) Systematic review and meta-analysis of the effectiveness and perinatal outcomes of COVID-19 vaccination in pregnancy. Nat Commun 13(1): 2414.
63. Ghesquiere L, Boivin G, Demuth B, Giguere Y, Forest JC, et al. (2024) Impact of COVID-19 and vaccination during pregnancy on placenta-mediated complications (COVIGRO study). J Obstet Gynaecol Can 46(4): 102291.
64. Jaswa EG, Cedars MI, Lindquist KJ, Bishop SL, Kim YS, et al. (2024) In utero exposure to maternal COVID-19 vaccination and offspring neurodevelopment at 12 and 18 months. JAMA Pediatr 178(3): 258-265.
65. Hui L, Marzan MB, Rolnik DL, Potenza S, Pritchard N, et al. (2023) Reductions in stillbirths and preterm birth in COVID-19-vaccinated women: a multicenter cohort study of vaccination uptake and perinatal outcomes. Am J Obstet Gynecol 228(5): 585.e1-585.e16.
66. Kachikis A, Pike M, Eckert LO, Roberts E, Frank Y, et al. (2024) Timing of maternal COVID-19 vaccine and antibody concentrations in infants born preterm. JAMA Netw Open 7(1): e2352387.
67. Shafiee A, Kohandel Gargari O, Teymouri Athar MM, Fathi H, Ghaemi M, et al. (2023) COVID-19 vaccination during pregnancy: a systematic review and meta-analysis. BMC Pregnancy Childbirth 23(1): 45.
68. Zhao Y, Zhao Y, Su X, Zhou Y, Zhang Z, et al. (2023) No association of vaccination with inactivated COVID-19 vaccines before conception with pregnancy complications and adverse birth outcomes: a cohort study of 5457 Chinese pregnant women. J Med Virol 95(4).
69. Lipkind HS, Vazquez Benitez G, DeSilva M, Vesco KK, Ackerman Banks C, et al. (2022) Receipt of COVID-19 vaccine during pregnancy and preterm or small-for-gestational-age at birth - Eight integrated health care organizations, United States, December 15, 2020-July 22, 2021. MMWR Morb Mortal Wkly Rep 71(1): 26-30.
70. Darwin KC, Kohn JR, Shippey E, Uribe KA, Gaur P, et al. (2023) Reduction in preterm birth among COVID-19-vaccinated pregnant individuals in the United States. Am J Obstet Gynecol MFM 5(10): 101114.
71. Torche F, Nobles J (2023) Vaccination, immunity, and the changing impact of COVID-19 on infant health. Proc Natl Acad Sci U S A 120(49): e2311573120.
72. Vesco KK, Denoble AE, Lipkind HS, Kharbanda EO, DeSilva MB, et al. (2024) Obstetric complications and birth outcomes after antenatal COVID-19 vaccination. Obstet Gynecol 143(6): 794-802.
73. Barros FC, Gunier RB, Rego A, Sentilhes L, Rauch S, et al. (2024) Maternal vaccination against COVID-19 and neonatal outcomes during Omicron: INTERCOVID-2022 study. Am J Obstet Gynecol 231(4): 460.e1-460.e17.
74. Du T, Qu Q, Zhang Y, Huang Q (2023) No observable influence of COVID-19 inactivated vaccines on pregnancy and birth outcomes in the first trimester of gestation. Expert Rev Vaccines 22(1): 900-905.
75. Facciolà A, Micali C, Visalli G, Venanzi Rullo E, Russotto Y, et al. (2022) COVID-19 and pregnancy: clinical outcomes and scientific evidence about vaccination. Eur Rev Med Pharmacol Sci 26(7): 2610-2626.
76. Ha L, Levian C, Greene N, Goldfarb I, Hirsch A, et al. (2023) Association between acceptance of routine pregnancy vaccinations and COVID-19 vaccine uptake in pregnant patients. J Infect 87(6): 551-555.
77. Blakeway H, Prasad S, Kalafat E, Heath PT, Ladhani SN, et al. (2022) COVID-19 vaccination during pregnancy: coverage and safety. Am J Obstet Gynecol 226(2): 236.e1-236.e14.
78. Carbone L, Trinchillo MG, Di Girolamo R, Raffone A, Saccone G, et al. (2022) COVID-19 vaccine and pregnancy outcomes: A systematic review and meta-analysis. Int J Gynaecol Obstet 159(3): 651-661.
79. Ramírez SI (2023) Prenatal care: an evidence-based approach. Am Fam Physician 108(2): 139-150.
80. Kalafat E, Heath P, Prasad S, O'Brien P, Khalil A (2022) COVID-19 vaccination in pregnancy. Am J Obstet Gynecol 227(2): 136-147.
81. Male V (2022) SARS-CoV-2 infection and COVID-19 vaccination in pregnancy. Nat Rev Immunol 22(5): 277-282.
82. Jamieson DJ, Rasmussen SA (2022) An update on COVID-19 and pregnancy. Am J Obstet Gynecol 226(2): 177-186.
83. Vesco KK, Denoble AE, Lipkind HS, Kharbanda EO, DeSilva MB, et al. (2024) Obstetric complications and birth outcomes after antenatal COVID-19 vaccination. Obstet Gynecol 143(6): 794-802.
84. Rahmati M, Yon DK, Lee SW, Butler L, Koyanagi A, et al. (2023) Effects of COVID-19 vaccination during pregnancy on SARS-CoV-2 infection and maternal and neonatal outcomes: A systematic review and meta-analysis. Rev Med Virol 33(3): e2434.
85. Fell DB, Dimanlig Cruz S, Regan AK, Håberg SE, Gravel CA, et al. (2022) Risk of preterm birth, small for gestational age at birth, and stillbirth after COVID-19 vaccination during pregnancy: population-based retrospective cohort study. BMJ 378.
86. Prasad S, Kalafat E, Blakeway H, Townsend R, O'Brien P, et al. (2022) Systematic review and meta-analysis of the effectiveness and perinatal outcomes of COVID-19 vaccination in pregnancy. Nat Commun 13(1): 2414.
87. Zhao Y, Su X, Zhou Y, Zhang Z, Zhang Y, et al. (2023) No association of vaccination with inactivated COVID-19 vaccines before conception with pregnancy complications and adverse birth outcomes: a cohort study of 5457 Chinese pregnant women. J Med Virol 95(4).
88. Goldshtein I, Steinberg DM, Kuint J, Chodick G, Segal Y, et al. (2022) Association of BNT162b2 COVID-19 vaccination during pregnancy with neonatal and early infant outcomes. JAMA Pediatr 176(5): 470-477.
89. Kachikis A, Pike M, Eckert LO, Roberts E, Frank Y, et al. (2024) Timing of maternal COVID-19 vaccine and antibody concentrations in infants born preterm. JAMA Netw Open 7(1): e2352387.
90. Hui L, Marzan MB, Potenza S, Rolnik DL, Said JM, et al. (2021) Collaborative maternity and newborn dashboard (CoMaND) for the COVID-19 pandemic: a protocol for timely, adaptive monitoring of perinatal outcomes in Melbourne, Australia. BMJ Open 11(11): e055902.