ArticleThe New England journal of medicine2013
Risk of fetal death after pandemic influenza virus infection or vaccination.
Article in The New England journal of medicine, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 119 papers, 7 of them syntheses that pooled it.
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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.
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Who cites it
119 citing papers in PubMed, 7 syntheses or guidelines pooled it, 298 citations in OpenAlex.
- Pooled it
- Pooled it
- Influenza Vaccine Efficacy and Effectiveness in Pregnant Women: Systematic Review and Meta-analysis.Maternal and child health journal · 2020Pooled it
- The safety of inactivated influenza vaccines in pregnancy for birth outcomes: a systematic review.Human vaccines & immunotherapeutics · 2019Pooled it
- Vaccines for preventing influenza in healthy adults.The Cochrane database of systematic reviews · 2018Pooled it
- Guideline
- Maternal influenza and birth outcomes: systematic review of comparative studies.BJOG : an international journal of obstetrics and gynaecology · 2017Pooled it
- Contribution of Serologic Assays in the Evaluation of Influenza Virus Infection Rates and Vaccine Efficacy in Pregnant Women: Report From Randomized Controlled Trials.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2017Trial
- Brief education to increase uptake of influenza vaccine among pregnant women: a study protocol for a randomized controlled trial.BMC pregnancy and childbirth · 2014Trial
- Influenza A virus infection induces immune dysregulation in the placenta and fetus without vertical transmission in nonhuman primates.Science advances · 2026Article
- Dipeptidylpeptidase 4 inhibition attenuates gestational pathologies via immune homeostasis restoration in the pulmonary-uterine axis.Nature communications · 2026Article
- Evaluating the Protective Effects of Influenza Vaccination in Pregnant Women and Their Infants: An Umbrella Review.Iranian journal of public health · 2025Review
- Mothers and mosquitoes: climate change contributes to the spread of vector-borne pathogens posing a substantial threat to pregnant women.Seminars in immunopathology · 2025Review
- Preexisting vaccine-primed heterosubtypic T cell immunity protects the maternal-fetal unit from adverse influenza outcomes in mice.The Journal of clinical investigation · 2025Article
- Maternal influenza vaccination during pregnancy and the risk of adverse pregnancy and birth outcomes.Frontiers in pharmacology · 2025Article
- Defining the balance between optimal immunity and immunopathology in influenza virus infection.Nature reviews. Immunology · 2024Review
- Risk of healthcare visits from influenza in subjects with diabetes and impacts of early vaccination.BMJ open diabetes research & care · 2024Article
- Influenza Virus Infection during Pregnancy as a Trigger of Acute and Chronic Complications.Viruses · 2022Review
- Article
- Influenza and Pertussis Maternal Vaccination Coverage and Influencing Factors in Spain: A Study Based on Primary Care Records Registry.International journal of environmental research and public health · 2022Article
59 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
19 authors at 5 institutions in 3 countries.
Funding
Abstract
backgroundDuring the 2009 influenza A (H1N1) pandemic, pregnant women were at risk for severe influenza illness. This concern was complicated by questions about vaccine safety in pregnant women that were raised by anecdotal reports of fetal deaths after vaccination.
methodsWe explored the safety of influenza vaccination of pregnant women by linking Norwegian national registries and medical consultation data to determine influenza diagnosis, vaccination status, birth outcomes, and background information for pregnant women before, during, and after the pandemic. We used Cox regression models to estimate hazard ratios for fetal death, with the gestational day as the time metric and vaccination and pandemic exposure as time-dependent exposure variables.
resultsThere were 117,347 eligible pregnancies in Norway from 2009 through 2010. Fetal mortality was 4.9 deaths per 1000 births. During the pandemic, 54% of pregnant women in their second or third trimester were vaccinated. Vaccination during pregnancy substantially reduced the risk of an influenza diagnosis (adjusted hazard ratio, 0.30; 95% confidence interval [CI], 0.25 to 0.34). Among pregnant women with a clinical diagnosis of influenza, the risk of fetal death was increased (adjusted hazard ratio, 1.91; 95% CI, 1.07 to 3.41). The risk of fetal death was reduced with vaccination during pregnancy, although this reduction was not significant (adjusted hazard ratio, 0.88; 95% CI, 0.66 to 1.17).
conclusionsPandemic influenza virus infection in pregnancy was associated with an increased risk of fetal death. Vaccination during pregnancy reduced the risk of an influenza diagnosis. Vaccination itself was not associated with increased fetal mortality and may have reduced the risk of influenza-related fetal death during the pandemic. (Funded by the Norwegian Institute of Public Health.).
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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.