ArticleAmerican journal of epidemiology2016
Risk of Preterm or Small-for-Gestational-Age Birth After Influenza Vaccination During Pregnancy: Caveats When Conducting Retrospective Observational Studies.
Article in American journal of epidemiology, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 35 papers, 2 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
35 citing papers in PubMed, 2 syntheses or guidelines pooled it, 67 citations in OpenAlex.
- Pooled it
- Effects of maternal influenza vaccination on adverse birth outcomes: A systematic review and Bayesian meta-analysis.PloS one · 2019Pooled it
- Trial
- Article
- Protecting pregnancy during pandemics: What recent outbreaks teach us.Human vaccines & immunotherapeutics · 2025Review
- Nonadjuvanted Bivalent Respiratory Syncytial Virus Vaccination and Perinatal Outcomes.JAMA network open · 2024Observational
- Defining and reporting adverse events of special interest in comparative maternal vaccine studies: a systematic review.Vaccine: X · 2024Review
- COVID-19 Vaccine Safety Surveillance in Early Pregnancy in the United States: Design Factors Affecting the Association Between Vaccine and Spontaneous Abortion.American journal of epidemiology · 2023Article
- Maternal Vaccination to Prevent Adverse Pregnancy Outcomes: An Underutilized Molecular Immunological Intervention?Journal of molecular biology · 2023Review
- Pregnancy, fetal, and neonatal outcomes after a first booster dose of covid-19 vaccine during pregnancy in Ontario, Canada: population based, retrospective cohort study.BMJ medicine · 2023Article
- Monitoring the safety of COVID-19 vaccines in pregnancy in the US.Human vaccines & immunotherapeutics · 2021Article
- Article
- Methodological frontiers in vaccine safety: qualifying available evidence for rare events, use of distributed data networks to monitor vaccine safety issues, and monitoring the safety of pregnancy interventions.BMJ global health · 2021Review
- Article
- Association of Inadvertent 9-Valent Human Papillomavirus Vaccine in Pregnancy With Spontaneous Abortion and Adverse Birth Outcomes.JAMA network open · 2021Article
- Educational note: addressing special cases of bias that frequently occur in perinatal epidemiology.International journal of epidemiology · 2021Article
- Associations Between Maternal Immunisation and Reduced Rates of Preterm Birth and Stillbirth: A Population Based Retrospective Cohort Study.Frontiers in immunology · 2021Article
- Individual and Neighborhood Factors Associated With Failure to Vaccinate Against Influenza During Pregnancy.American journal of epidemiology · 2020Article
- Analysis of perinatal risk factors for small-for-gestational-age and appropriate-for-gestational-age late-term infants.Experimental and therapeutic medicine · 2020Article
- Chorioamnionitis: Case definition & guidelines for data collection, analysis, and presentation of immunization safety data.Vaccine · 2019Review
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Authors and funding
13 authors.
Funding
Abstract
Vaccines are increasingly targeted toward women of reproductive age, and vaccines to prevent influenza and pertussis are recommended during pregnancy. Prelicensure clinical trials typically have not included pregnant women, and when they are included, trials cannot detect rare events. Thus, postmarketing vaccine safety assessments are necessary. However, analysis of observational data requires detailed assessment of potential biases. Using data from 8 Vaccine Safety Datalink sites in the United States, we analyzed the association of monovalent H1N1 influenza vaccine (MIV) during pregnancy with preterm birth (<37 weeks) and small-for-gestational-age birth (birth weight < 10th percentile). The cohort included 46,549 pregnancies during 2009-2010 (40% of participants received the MIV). We found potential biases in the vaccine-birth outcome association that might occur due to variable access to vaccines, the time-dependent nature of exposure to vaccination within pregnancy (immortal time bias), and confounding from baseline differences between vaccinated and unvaccinated women. We found a strong protective effect of vaccination on preterm birth (relative risk = 0.79, 95% confidence interval: 0.74, 0.85) when we ignored potential biases and no effect when accounted for them (relative risk = 0.91; 95% confidence interval: 0.83, 1.0). In contrast, we found no important biases in the association of MIV with small-for-gestational-age birth. Investigators conducting studies to evaluate birth outcomes after maternal vaccination should use statistical approaches to minimize potential biases.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.