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COVID-19 vaccination during pregnancy or lactation and infant growth and health care utilization
Elyse O Kharbanda1, Jingran Cao1, Gabriela Vazquez-Benitez1
1Pregnancy and Child Health Research Center, HealthPartners Institute, Minneapolis, MN.
Objective:
To evaluate associations between COVID-19 vaccination during pregnancy or lactation and infant growth and health care utilization.
Methods:
This observational study from 4 U.S. health systems included singleton pregnancies with linked live births from December 2020-September 2022; eligibility varied by exposure and outcome. COVID-19 vaccinations were identified from electronic health records, claims, and immunization information systems. Infant health care utilization was based on number of outpatient (OP) or emergency department (ED) visits while faltering weight was identified from weight-for-length percentiles. Outcomes were compared for those with and without COVID-19 vaccine exposures ≥20 weeks gestation or during lactation and within 90 days following delivery. For OP and ED visits, we calculated adjusted rate ratio (aRR) and 95% confidence intervals (CI) using negative binomial regression. For faltering weight, we calculated adjusted prevalence ratio (aPR) and 95% CIs using Poisson regression.
Results:
Among 7,141 eligible mother-infant dyads, aRRs for infant OP and ED visits by 6 months following COVID-19 vaccination during pregnancy were 1.03 (95% CI 0.99-1.06) and 1.03 (0.83-1.27), respectively. Among 11,921 eligible mother-infant dyads the aPR for faltering weight by 12 months following vaccination during pregnancy was 1.07 (0.89-1.28). Among 8,442 lactating mother-infant dyads, aRRs for infant OP and ED visits within 90 days of postpartum vaccination were 1.03 (0.98-1.08) and 1.05 (0.70-1.56), respectively. Among 10,181 mother-infant dyads, the aPR for faltering weight following vaccination during lactation was 0.62 (0.48-0.79).
Conclusion:
COVID-19 vaccination during pregnancy or lactation was not associated with adverse infant growth or health care utilization.
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