These findings, recently published in The BMJnorth_eastexternal link, can help inform evidence-based decision-making about the risks and benefits of vaccination against COVID-19 during pregnancy. “Our study found no evidence of an increased risk of preterm birth, very preterm birth, small gestational age at birth, or stillbirth after vaccination against COVID-19 during pregnancy. The results of this study provide further evidence for caregivers and pregnant women regarding the safety of vaccination for COVID-19 during pregnancy,” said lead author Dr. Medicine. SARS-CoV-2 infection during pregnancy has been associated with higher risks of complications, including hospitalization and death of pregnant women, as well as preterm birth and stillbirth. Vaccination against COVID-19 during pregnancy has been shown to be effective against COVID-19 in pregnant people as well as their newborns, but data on pregnancy outcomes after vaccination against COVID-19 during pregnancy from large studies are limited. In a project supported by the Public Health Service of Canada through the Vaccine Surveillance Reference Group and the Immunity Task Force on COVID-19, researchers set out to assess the risk of preterm delivery, small for gestational age at birth and stillbirth after the COVID-19. vaccination during pregnancy. They used the BORN Ontario Birth Registry, the CHEO-based provincial birth registry, to identify all live and stillborn infants with a gestational age of at least 20 weeks or a birth weight of at least 500 grams in Ontario, Canada between May 1 and December. 31, 2021. This information was then linked to COVaxON, the province’s immunization database against COVID-19. A wide range of potentially important factors were taken into account, including maternal age at delivery, prepregnancy body mass index, reported smoking or substance use during pregnancy, pre-existing health conditions, number of previous live births, and of stillbirths, area of residence and income. Of the 85,162 births, 43,099 occurred to people who received one or more doses of the COVID-19 vaccine during pregnancy – 42,979 (99.7%) received an mRNA vaccine, mostly Pfizer-BioNTech or Moderna. (See Figure 1) The study found that vaccination during pregnancy was not associated with an increased risk of overall preterm birth (6.5% among vaccinated vs. 6.9% among unvaccinated), spontaneous preterm birth (3.7% vs. 4.4 %) or very premature birth (0.59% vs. 0.89%). No increase in the risk of small for gestational age at birth (9.1% vs. 9.2%) or stillbirth (0.25% vs. 0.44%) was found. Findings were similar regardless of vaccination stage (trimester) of pregnancy, number of doses received during pregnancy, or mRNA vaccine product received. There are still some important unanswered questions that need future research, such as the evaluation of COVID-19 vaccination before pregnancy or at the time of conception and evaluation of non-mRNA vaccines used during pregnancy. The researchers noted “Future studies to evaluate similar outcomes after immunization with nonmRNA types of COVID-19 vaccines during pregnancy should be a research priority.” Report: Fell DB, Dimanlig-Cruz S, Regan AK, et al. Risk of preterm delivery, small for gestational age at birth and stillbirth after vaccination against Covid-19 during pregnancy: a population-based retrospective cohort study. BMJ. 2022;378:e071416. doi: 10.1136/bmj-2022-071416 This article has been republished from the following materials. Note: material may have been edited for length and content. For more information, please contact the cited source.
