FULL CLAIM: COVID-19 vaccination of pregnant women is connected to an increase in U.S. infant mortality rate in 2022
REVIEW
Introduction
The safety of COVID-19 vaccines for pregnant women and their unborn children has been a recurring subject of misinformation, as Health Feedback documented.
In a recent illustration of this, a post circulated on social media in November 2023 that assembled headlines from several CNN articles published between March 2021 and November 2023. The first four headlines dealt with recommendations from public health agencies for pregnant women to get vaccinated against COVID-19. The post highlighted the words “vaccines” and “vaccinated” from these headlines and connected them to the headline at the bottom, stating “US infant mortality rate rises for first time in more than 20 years”.
Thus, the post clearly implies that COVID-19 vaccination is causally associated with this observed increase in infant mortality. However, this is directly contradicted by a growing amount of data, as we explain below.
CNN’s article reported on the release by the U.S. Centers for Disease Control and Prevention (CDC) of the U.S. provisional infant mortality rate for 2022. The CDC defines infant death as the death of a child before their first birthday. The data indicated that the infant mortality rate rose 3%, from 5.44 deaths per 1,000 live births in 2021 to 5.60 per 1,000 live births in 2022.
These figures drew attention because it was the biggest increase in infant mortality rate seen in twenty years. Overall, the infant mortality rate in the U.S. has been steadily declining each year. Although the rate increased year-on-year from 2004 to 2005, 2006 to 2007, and 2014 to 2015, these increases were limited to 1% before decreasing again[1-4]. One needs to go back to the period between 2001 and 2002 to observe an increase of the same scale observed between 2021 and 2022.
Figure 1. Infant mortality rate in the U.S. expressed as the number of infant deaths per 1,000 live births. Neonatal mortality is the mortality of children younger than 28 days old. Postneonatal mortality is the mortality of children aged between 28 days and one year. Source: National Vital Statistics Reports.
COVID-19 vaccines aren’t responsible for the increase infant mortality in 2022
However, there is no data supporting the claim that COVID-19 vaccines had anything to do with it. First, the infant mortality rate reported by the CDC isn’t stratified by the mothers’ vaccination status. This means that we cannot compare the mortality rate in infants born to vaccinated mothers with that in infants born to unvaccinated mothers. Since we cannot do so with these data, it is simply impossible to draw any definitive conclusions on vaccine safety from the infant mortality rate report.
Also, one could assume that, if indeed vaccines increased infant mortality, then we would expect to see greater infant mortality the higher a state’s vaccine coverage is.
However, the CDC report indicates that the increase in mortality rate was only significant in Georgia, Iowa, Missouri, and Texas. Yet, all of these states reported vaccination coverage lower than the national average. Indeed, the percentage of vaccinated people aged above 12 years in Georgia, Iowa, Missouri, and Texas are 66%, 73%, 67%, and 73%, respectively. By comparison, the national average for this group in the population is 78%. Although not conclusive on its own, the absence of an association between infant mortality and vaccine coverage speaks against the claim.
More importantly, there is now a broad scientific literature unambiguously showing that COVID-19 vaccines are safe for mothers and their babies.
A study on 24,000 newborns in Israel showed no increase in infant mortality among children born to vaccinated mothers[5]. A larger study in over 140,000 infants from Canada showed that infants born to vaccinated mothers were in fact at a lower risk of neonatal deaths than infants born to unvaccinated mothers[6].
There is also ample evidence that COVID-19 vaccines don’t increase the risk of stillbirth[7-9] or pregnancy complications like severe neonatal morbidity[6], small for gestational age (SGA), and preterm births[5,7-10]. While SGA and preterm births aren’t necessarily fatal, they are associated with a higher risk of infant mortality[11,12]. The fact that COVID-19 vaccines don’t increase the odds of SGA or preterm births thus confirm their safety profile.
Not only are COVID-19 vaccines safe for pregnant women, but they are also beneficial. Indeed, pregnant women who get COVID-19 are at a higher risk of developing severe disease, associated with ICU admission, need for mechanical ventilation, or death[13,14]. Furthermore, getting COVID-19 while pregnant also increases the risk of negative pregnancy outcomes such as stillbirth or neonatal mortality[14-18]. Thus, those vaccines offer an effective protection against COVID-associated pregnancy complications.
What could explain the increase in infant mortality rate in 2022?
So far, the results are only preliminary and a more in-depth study would be required to arrive at more reliable conclusions. Danielle Ely, a health statistician and lead author of the CDC report, told Associated Press that researchers still couldn’t establish whether the rise was a one-year statistical blip or indicated an actual change in trend.
That said, it should be noted that year-on-year increases of that magnitude are rare, but not unheard of. It already happened in 2001, as we mentioned earlier. One possible contributor to this increase is a surge of respiratory infections such as the flu and the Respiratory Syncytial Virus (RSV), as Eric Eichenwald, a neonatologist at the Children’s Hospital of Philadelphia, explained to STAT News.
Another possible factor is the deteriorating access to healthcare for certain groups in the population.
Sandy Chung, the president of the American Academy of Pediatrics, told CNN that “we know that for people who live in or near poverty and for certain racial and ethnic groups there are significant challenges with getting access to a doctor or getting treatments […] This can lead to moms and babies showing up for care when they are sicker and more likely have serious outcomes, even death”.
Conclusion
In summary, scientific research overwhelmingly shows that COVID-19 vaccines are safe for pregnant women and for their unborn children. COVID-19 vaccines protect from severe disease and thus reduce COVID-associated risks during pregnancy. The infant mortality statistics for 2022 still need to be consolidated, and researchers still don’t know for sure the reasons behind this 3% increase, and if this is simply a blip in the data or an actual trend.
Experts have proposed certain explanations for this increase, although arriving at reliable conclusions requires additional research. However, claims or suggestions that COVID-19 vaccines are responsible for the rise in infant mortality aren’t in line with the available scientific data showing no association between the two.
REFERENCES
- 1 – Mathews et al. (2004) Infant mortality statistics from the 2002 period: linked birth/infant death data set. National Vital Statistics Reports
- 2 – Mathews et al. (2008) Infant mortality statistics from the 2005 period linked birth/infant death data set. National Vital Statistics Reports
- 3 – Mathews et al. (2011) Infant mortality statistics from the 2007 period linked birth/infant death data set. National Vital Statistics Reports
- 4 – Xu et al. (2016) Mortality in the United States, 2015. NCSHS Data Brief
- 5 – Goldshtein et al. (2022) Association of BNT162b2 COVID-19 Vaccination During Pregnancy With Neonatal and Early Infant Outcomes. JAMA Pediatrics
- 6 – Jorgensen et al. (2023) Newborn and Early Infant Outcomes Following Maternal COVID-19 Vaccination During Pregnancy. JAMA Pediatrics
- 7 – Piekos et al. (2023) Effect of COVID-19 vaccination and booster on maternal–fetal outcomes: a retrospective cohort study. The Lancet Digital Health
- 8 – Tormen et al. (2023) Effectiveness and safety of COVID-19 vaccine in pregnant women: A systematic review with meta-analysis. BJOG
- 9 – Fell et a. (2022) Risk of preterm birth, small for gestational age at birth, and stillbirth after covid-19 vaccination during pregnancy: population based retrospective cohort study. The British Journal of Medicine
- 10 – Lipkind 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. Morbidity and Mortality Weekly Report
- 11 – Ludvigsson et al. (2018) Small for gestational age and risk of childhood mortality: A Swedish population study. PLoS Medicine
- 12 – Lindqvist & Molin (2005) Does antenatal identification of small-for-gestational age fetuses significantly improve their outcome? Ultrasounds in Obstetrics and Gynecology
- 13- Zambrano et al. (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. Morbidity and Mortality Weekly Report
- 14 – Allotey et al. (2020) Clinical manifestations, risk factors, and maternal and perinatal outcomes of coronavirus disease 2019 in pregnancy: living systematic review and meta-analysis. British Medical Journal
- 15 – DeSisto et al. (2021) Risk for Stillbirth Among Women With and Without COVID-19 at Delivery Hospitalization — United States, March 2020–September 2021. Morbidity and Mortality Weekly Report
- 16 – Stock et al. (2022) SARS-CoV-2 infection and COVID-19 vaccination rates in pregnant women in Scotland. Nature medicine
- 17 – Villar et al. (2023) Pregnancy outcomes and vaccine effectiveness during the period of omicron as the variant of concern, INTERCOVID-2022: a multinational, observational study. The Lancet
- 18 – Villar et al. (2021) Maternal and Neonatal Morbidity and Mortality Among Pregnant Women With and Without COVID-19 Infection: The INTERCOVID Multinational Cohort Study. JAMA Pediatrics
