The largest study conducted to date, involving nearly 200,000 newborns, to evaluate any potential risks associated with maternal vaccination against Covid-19, found no increased risks for the infants whose mothers received the vaccine during pregnancy.
The study published in the prestigious journal JAMA was conducted by collaborating researchers from Sweden and Norway. The study titled: "Neonatal Outcomes After Covid-19 Vaccination in Pregnancy" was authored by Mikael Norman, Maria C. Magnus, Jonas Söderling, Petur B. Juliusson, Lars Navér, Anne K. Örtqvist, Siri Håberg, Olof Stephansson.
Contrary to concerns, the study found that the infants born to vaccinated mothers exhibited a lower likelihood of experiencing serious complications, including mortality. Remarkably, the mortality rate was halved in babies born to vaccinated mothers compared to those born to unvaccinated mothers.
Prof Mikael Norman, leading the research and a distinguished figure in pediatrics and neonatology at Karolinska Institutet, says that the findings persist despite exhaustive analyses, suggesting that direct vaccine effects are improbable. Previous studies have confirmed that the vaccine does not traverse the placenta nor appear in umbilical cord blood.
The comprehensive study, encompassing 98 percent of newborns born after the availability of vaccines, examined various complications affecting newborns. Strikingly, infants born to vaccinated mothers exhibited significantly lower rates of cerebral hemorrhages and hypoxia-ischemic conditions of the brain, compared to their counterparts born to unvaccinated mothers.
While the pandemic may be receding, the implications of this study remain profound for healthcare providers, policymakers, and expectant mothers worldwide. The reassurance of vaccine safety during pregnancy, underscored by this research, is invaluable, particularly as Covid-19 continues to pose a threat.
The study was primarily supported by Region Stockholm and Karolinska Institutet, along with contributions from the Childhood Foundation of the Swedish Order of Freemasons, NordForsk, and the Norwegian Research Council. The researchers declare no conflicts of interest.
Pfizer's Comirnaty and Moderna's Spikevax mRNA vaccines were the first Covid-19 vaccines approved, with Pfizer's approval on December 21, 2020, and Moderna's shortly after on January 6, 2021.
These mRNA vaccines were the only ones recommended for pregnant women in Sweden and Norway.
Initially, vaccination was restricted to pregnant women at high risk for Covid-19, but general vaccination for pregnant women was recommended from May 2021 in Sweden and August 2021 in Norway.
Table: Complications Rates in Newborns