396 - Maternal Vaccination During Pregnancy and Newborn Immunization in the Bronx

Publication Number: 2385.396

Madeline M. Grbic, Albert Einstein College of Medicine, The Bronx, NY, United States; Sheri L. Nemerofsky, The Children's Hospital at Montefiore, Bronx, NY, United States; Shipra Gupta, Children's Hospital At Montefiore, Bronx, NY, United States

Background: Maternal vaccination protects both mothers and newborns by reducing the risk of maternal infection and providing passive immunity to infants. Vaccines such as influenza and Tdap are critical to prevent severe illness in mothers and newborns. Recently, maternal respiratory syncytial virus (RSV) vaccination and an infant monoclonal antibody (nirsevimab) were added and recommended to protect newborns against RSV.

Objective: This study aims to assess maternal and newborn immunization rates in the Bronx during respiratory virus season and evaluate associations with social and demographic factors.

Design/Methods: This retrospective cohort study examined immunization uptake among birthing parents in the Bronx, NY, who delivered between October 15, 2024, and March 31, 2025. Data collected included maternal age, primary language, ethnicity, race, insurance status, and parity. Immunization records were reviewed for maternal influenza, Tdap, and RSV vaccines, as well as newborn nirsevimab and hepatitis B immunization. Chi-square and t-tests were used for analysis.

Results: There were 528 maternal and newborn paired charts reviewed, and 29 paired charts were excluded due to missing demographic information, and 1 paired chart was excluded due to neonatal demise. Demographics and vaccine uptake information are shown in Table 1. 19.5% of patients received all 3 vaccines. Mean maternal age was significantly higher in those who received each vaccine; Tdap (29.7y vs 27.8y), influenza (30.1y vs 28.6y) and the maternal RSV (29.9y vs 28.7y). Non-English speakers were more likely to receive Tdap (74% vs 64.6%), influenza (45.7% vs 29.5%) and protect their newborns from RSV (84.9% vs 70.8%). Multiparous women were more likely to receive the influenza vaccine (38.9% vs 29.5%). There were no statistically significant differences between ethnicity, race, and insurance for Tdap and influenza vaccines. Non-English speakers and Medicaid insured patients were more likely to consent for the Hepatitis B vaccine. In total, 93.6% of newborns received the Hepatitis B vaccine and 75.7% of newborns were protected from RSV, 43.5% through maternal RSV vaccination and 56.4% by nirsevimab.

Conclusion(s): Most pregnant women in the Bronx are not protected from vaccine-preventable respiratory diseases. Nearly all newborns were protected from Hepatitis B and RSV. Targeted vaccine education efforts for pregnant people in the Bronx, particularly for younger women and first-time mothers, may increase maternal vaccinations. Further research is needed to decrease maternal vaccine hesitancy.

Table 1. Maternal Demographics and Vaccine Uptake
^ includes only infants eligible for the newborn vaccine (excludes those whose mother received maternal vaccine)