November 8, 2023
Medpage Today shares results from a study into maternal mRNA vaccination during pregnancy. The Canadian cohort study revealed COVID-19 vaccinations during pregnancy were associated with lower risks of poor neonatal outcomes, including neonatal death. No associations were seen between maternal vaccination during pregnancy and neonatal readmission or six-month hospital admission.
The study is further reassurance of maternal mRNA COVID-19 vaccine safety for mothers, newborns and infants. Compared with infants not exposed to the mRNA vaccine, in utero exposure to one or more doses led to lower risks severe neonatal morbidity (7.3% vs 8.3%), neonatal death (0.09% vs 0.16%), and NICU admission (11.4% vs 13.1%). Study authors noted the results were consistent with documented association of severe outcomes associated with COVID-19 during pregnancy.
The study included 142,006 infants between May 1, 2021 and September 2, 2022. Among vaccinated mothers, 48.6% had received one dose of a mRNA COVID-19 vaccine, 49.6% had received two doses, and 1.8% had received three doses. More than two-thirds (68%) received the Pfizer-BioNTech vaccine for all doses. The trimester breakdown was about a third in the first trimester, more than half in the second trimester and 44.5% in the third.
Poor outcomes included gestational age less than 32 weeks, respiratory problems, neurological problems, birth trauma, ventilation, arterial catheter placement, and death among several others.
PIDS member Catherine Healy co-authored an accompanying editorial. It said, “Safe and effective vaccines such as the COVID-19 vaccine should provide confidence in the maternal vaccination program where maternal vaccines provide protection for mothers and neonates against potentially devastating infections…Reasons for these poor vaccination rates include safety concerns despite years of safety data, lack of awareness of risk for severe morbidity and mortality associated with influenza in pregnancy, and lack of knowledge that maternal vaccination protects the newborn when the newborn is most vulnerable before vaccination at 6 months of age…Studies consistently demonstrate … that the single most important factor in vaccination uptake in all populations is receiving a strong recommendation from a trusted health care professional, and for pregnant women, this patient-clinician relationship is particularly strong. When this recommendation is combined with easy access, preferably on-site but at least convenient for uptake during a visit, vaccine administration in pregnancy is most likely to occur.”