In a recent study published in the journal Dr Jama Network, The researchers investigated the possible association between administration of the COVID-19 mRNA vaccine in pregnant women and adverse events in their newborns. They used a broad sample cohort consisting of 94,303 cases and 102,167 controls and found that not only were mRNA vaccines associated with adverse outcomes, but they were also shown to reduce the odds ratios (ORs) for neonatal cerebral ischemia and hypoxic-ischemic encephalopathy. Bleeding, and mortality. These results support vaccination efforts and vaccination recommendations during pregnancy conducted by various authorities.
Study: Neonatal outcomes after COVID-19 vaccination during pregnancy. Image credit: Unai Whiz Photography / Shutterstock
Why do pregnant women need the COVID-19 vaccine?
The coronavirus disease 2019 (COVID-19) pandemic has been one of the most devastating socio-economic, medical and infrastructural global events in recent times. Since its discovery in Wuhan, China in late 2019, the pandemic has infected more than 700 million people and claimed nearly 7 million lives. Fortunately, global vaccination efforts have made great strides in limiting virus transmission and preventing new outbreaks. Mono- and polyvalent messenger RNA (mRNA) vaccines have proven particularly effective in controlling the spread of disease.
Studies elucidating the effects of the COVID-19 vaccine during pregnancy have shown that the vaccine is an effective form of anti-COVID-19 immunization for both mothers and their unborn/newborn babies, prompting various world authorities to recommend its use. Unfortunately, previous literature aimed at evaluating vaccine safety in this small group has used limited sample sizes, thereby limiting their analytical power and allowing for debate by anti-vaccination camps despite their generally positive results.
Unconfirmed reports of possible neonatal brain lesions have prompted authorities and even physicians to express concern about the need for vaccination during pregnancy. Elucidating the benefits of vaccination during pregnancy and establishing their safety in a large-cohort case-control study will silence criticism and may lead to beneficial anti-COVID-19 interventions in the future.
About the study
In the current study, researchers conducted a comprehensive evaluation of the neonatal safety of mRNA vaccines to address concerns raised by authorities, physicians, and anti-vaccine groups about the need for vaccines received during pregnancy. Because the potential for vaccine-related neonatal brain lesions is a recurring claim, this study highlights neonatal cerebrovascular outcomes.
The study sample group was derived from a population-based cohort study conducted in Norway and Sweden that included all live births at 22 weeks of age or older, including newborns exhibiting congenital disabilities as defined by the European Network of Population-Based Registries for Epidemiological Surveillance. Congenital disability. Because this work focused on the safety of mRNA vaccines, vaccination data for other vaccine types were excluded from the analysis. Applying exclusion criteria still accounted for 97.4% and 98.6% of all live births in Sweden and Norway, respectively.
The study was from January 2021 to January 2023, during which 94,303 (vaccinated) cases and 102,167 (unvaccinated) controls were born. Demographics (ethnicity, education level, living with a partner, age, parity, smoking status, and body mass index [BMI]) and treatment (pregnancy comorbidities, season of gestation, gestational diabetes, multiple or singleton pregnancy, mode of delivery, and COVID-19 infection status) were collected from eight different national registries using unique personal identification numbers. Vaccination data included number of doses of mRNA vaccine received (before and during pregnancy), vaccine manufacturer, birth (days) since last vaccination, and time since conception (days) since last vaccination.
“Exposure was vaccination with mRNA vaccine against COVID-19 during pregnancy, regardless of previous mRNA vaccination, number of doses during pregnancy, or vaccine manufacturer. Vaccination during pregnancy was defined as vaccination anytime between conception and the date of delivery. The vaccines recommended for pregnant individuals are 2 mRNA vaccines manufactured by Pfizer-BioNTech (BNT162b2) and Moderna (mRNA-1273).
All outcomes were defined and measured based on the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision Code. Associations were estimated using multivariable analysis adjusting for covariates. Odds ratios (ORs) were calculated using logistic regression. Data from Sweden and Norway were first analyzed independently, then pooled and reanalyzed.
Study findings and conclusions
No adverse neonatal outcomes of vaccination were observed. In contrast, infants born to mothers who received anti-COVID-19 mRNA vaccine during pregnancy were less likely to be preterm, have lower Apgar scores, or be born small for gestational age (SGA). Encouragingly, vaccination was associated with a lower OR of more neonatal nontraumatic intracranial hemorrhage and neonatal death. If the vaccine is administered during the second trimester, the risk of cerebral ischemia and hypoxic-ischemic encephalopathy is further reduced.
“This large population-based safety study found no evidence of increased adverse neonatal events among infants born to individuals vaccinated against COVID-19 during pregnancy. In contrast, exposure to COVID-19 vaccination during pregnancy was associated with increased rates of nontraumatic intracranial hemorrhage, hypoxic-ischemic encephalopathy, and neonatal mortality.
These findings may help silence anti-vaccination critics and address the concerns of authorities and physicians that COVID-19 mRNA vaccines are safe and beneficial for use during pregnancy. Although vaccinated mothers should be closely monitored, these findings pave the way for renewed vaccination efforts, which may lead to more ongoing progress in putting the epidemic at rest.