Adverse events following administration to pregnant women of influenza A (H1N1) 2009 monovalent vaccine reported to the Vaccine Adverse Event Reporting System

Immunization Safety Office, Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
American journal of obstetrics and gynecology (Impact Factor: 4.7). 06/2011; 205(5):473.e1-9. DOI: 10.1016/j.ajog.2011.06.047
Source: PubMed

ABSTRACT The objective of the study was to evaluate and summarize reports to the Vaccine Adverse Event Reporting System (VAERS), a spontaneous reporting system, in pregnant women who received influenza A (H1N1) 2009 monovalent vaccine to assess for potential vaccine safety problems.
We reviewed reports of adverse events (AEs) in pregnant women who received 2009-H1N1 vaccines from Oct. 1, 2009, through Feb. 28, 2010.
VAERS received 294 reports of AEs in pregnant women who received 2009-H1N1 vaccine: 288 after inactivated and 6 after the live attenuated vaccines. Two maternal deaths were reported. Fifty-nine women (20.1%) were hospitalized. We verified 131 pregnancy-specific outcomes: 95 spontaneous abortions (<20 weeks); 18 stillbirths (≥20 weeks); 7 preterm deliveries (<37 weeks); 3 threatened abortions; 2 preterm labor; 2 preeclampsia; and 1 each of fetal hydronephrosis, fetal tachycardia, intrauterine growth retardation, and cleft lip.
Review of reports to VAERS following H1N1 vaccination in pregnant women did not identify any concerning patterns of maternal or fetal outcomes.

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Available from: Pedro L Moro, Dec 24, 2013
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    • "Studies of over 1000 women from Italy, France, Scotland, and the United Kingdom reported no serious adverse events among pregnant women or their neonates, with no significant differences in adverse birth outcomes and congenital anomaly rates compared with the background rates in the general population.53–56 A published review of reports to VAERS also concluded that there was no concerning pattern of maternal or fetal outcomes among women who were vaccinated during pregnancy or their children.57 "
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    ABSTRACT: Influenza poses unique risks to pregnant women, who are particularly susceptible to morbidity and mortality. Historically, pregnant women have been overrepresented among patients with severe illness and complications from influenza, and have been more likely to require hospitalization and intensive care unit admission. An increased risk of adverse outcomes is also present for fetuses/neonates born to women affected by influenza during pregnancy. These risks to mothers and babies have been observed during both nonpandemic and pandemic influenza seasons. During the H1N1 influenza pandemic of 2009-2010, pregnant women were more likely to be hospitalized or admitted to intensive care units, and were at higher risk of death compared to nonpregnant adults. Vaccination remains the most effective intervention to prevent severe illness, and antiviral medications are an important adjunct to ameliorate disease when it occurs. Unfortunately, despite national guidelines recommending universal vaccination for women who are pregnant during influenza season, actual vaccination rates do not achieve desired targets among pregnant women. Pregnant women are also sometimes reluctant to use antiviral medications during pregnancy. Some of the barriers to use of vaccines and medications during pregnancy are a lack of knowledge of recommendations and of safety data. By improving knowledge and understanding of influenza and vaccination recommendations, vaccine acceptance rates among pregnant women can be improved. Currently, the appropriate use of vaccination and antiviral medications is the best line of defense against influenza and its sequelae among pregnant women, and strategies to increase acceptance are crucial. This article will review the importance of influenza in pregnancy, and discuss vaccination and antiviral medications for pregnant women.
    International Journal of Women's Health 07/2014; 6(1):681-689. DOI:10.2147/IJWH.S47235
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    • "In fact, because of potential impact on the fetus, in our specialty, safety concerns can be amplified both for patients and providers for immunizations recommend during pregnancy [5–7]. We have seen that data generated from VAERS is able to reinforce the safety profile for recommending vaccines during pregnancy, including H1N1 and Tdap [8–10]. With increased reporting to VAERS, the data base will become more robust. "
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    ABSTRACT: Background: Obstetrician-gynecologists are increasingly called upon to be vaccinators as an essential part of a woman's primary and preventive health care. Despite the established safety of vaccines, vaccine adverse events may occur. A national Vaccine Adverse Event Reporting System (VAERS) is a well-established mechanism to track adverse events. However, we hypothesized that many obstetrician-gynecologists are naive to the role and use of VAERS. Methods: We devised a ten-question survey to a sample of ACOG fellows to assess their knowledge and understanding of VAERS. We performed descriptive and frequency analysis for each of the questions and used one-way analysis of variance for continuous and chi-squared for categorical variables. Results: Of the 1000 fellows who received the survey, 377 responded. Only one respondent answered all nine knowledge questions correctly, and 9.2% of physicians had used VAERS. Older physicians were less familiar with VAERS in general and with the specific objectives of VAERS in particular (χ(2) = 10.7, P = .005). Conclusions: Obstetrician-gynecologist familiarity with VAERS is lacking. Only when the obstetrician-gynecologist is completely knowledgeable regarding standard vaccine practices, including the availability and use of programs such as VAERS, will providers be functioning as competent and complete vaccinators.
    Infectious Diseases in Obstetrics and Gynecology 09/2013; 2013:285257. DOI:10.1155/2013/285257
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    ABSTRACT: In 2009, the Dutch government advised pregnant women to get vaccinated against influenza A (H1N1). A study was set up to gain insight into vaccination coverage and reasons why pregnant women seek vaccination or not. We invited 14,529 pregnant women to complete an internet survey on vaccination during pregnancy in general and against 2009 influenza A (H1N1). Differences in background characteristics between unvaccinated and vaccinated women were investigated. Prediction analyses were carried out to determine which survey statement had the greatest impact on vaccination status or intention to get vaccinated during pregnancy. Of the 2993 included respondents, 63% reported to be vaccinated against 2009 influenza A (H1N1). Vaccination coverage was higher among older birth cohorts, women who had been pregnant before, women with underlying medical conditions, and women who reported no defined 'life philosophy'. Protection of the child (after birth), the government's advice and possible harmful effects of the vaccine for the unborn child had the greatest predictive value for vaccination status. With regards vaccination during future pregnancies, 39% had a positive intention to obtain vaccination and 45% were neutral. The government's advice was the strongest predictor for intention. Furthermore, women expressed concern over lack of sufficient knowledge about vaccine safety. A considerable number of pregnant women in the Netherlands reported to be vaccinated against 2009 influenza A (H1N1). The challenge for the government in the future will be to provide pregnant women and health care professionals with sufficient and clear information about disease severity and the benefits and safety of vaccination.
    Vaccine 02/2012; 30(18):2892-9. DOI:10.1016/j.vaccine.2012.02.030 · 3.62 Impact Factor
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