Factors associated with COVID-19 vaccination among pregnant women in Rio De Janeiro City, Brazil

Abstract

COVID-19 vaccination during pregnancy is safe and effective in reducing the risk of complications. However, the uptake is still below targets worldwide. This study aimed to explore the factors associated with COVID-19 vaccination uptake among pregnant women since data on this topic is scarce in low-to-middle-income countries. A retrospective cohort study included linked data on COVID-19 vaccination and pregnant women who delivered a singleton live birth from August 1, 2021, to July 31, 2022, in Rio de Janeiro City, Brazil. Multiple logistic regression was performed to identify factors associated with vaccination during pregnancy, applying a hierarchical model and describing odds ratio with 95% confidence intervals. Of 65,304 pregnant women included in the study, 53.0% (95% CI, 52-53%) received at least one dose of COVID-19 vaccine during pregnancy. Higher uptake was observed among women aged older than 34 (aOR 1.21, 95%CI 1.15-1.28), black (aOR 1.10, 1.04-1.16), or parda/brown skin colour (aOR 1.05, 1.01-1.09), with less than eight years of education (aOR 1.09, 1.02-1.17), living without a partner (aOR 2.24, 2.16-2.34), more than six antenatal care appointments (aOR 1.92, 1.75-2.09), and having a previous child loss (OR 1.06, 1.02-1.11). These results highlight the need for targeted educational campaigns, trustful communication, and accessibility strategies for specific populations to improve vaccination uptake during pregnancy.

Figure 1

A conceptual framework describing factors that can contribute to COVID-19 vaccine uptake during pregnancy. The variables highlighted were included for analysis in this study.

Figure 2

Flowchart demonstrating the study population selection.

Figure 3

COVID-19 maternal vaccination by month of delivery and number of doses.

Figure 4

Forest plot of the magnitude of association between the factors associated with the uptake of the COVID-19 vaccine during pregnancy. Ref: variable used as the reference in the multiple logistic regression. Model 1: included socioeconomic (age, education, self-identified skin colour, marital status) Model 2: included obstetric (the total number of antenatal care appointments, the number of previous live births, the number of previous child loss) and socioeconomic.Month-year of birth and the gestational week at delivery are included as confounding variables in both models.