Senior Director, Epidemiology Syneos Health, United States
Background: Immunizing pregnant populations has increasingly been used to protect the mother, fetus, and infant from infectious diseases. Maternal antibodies serve as neonates’ primary source of protection during their first weeks of life when they are most vulnerable. Tdap and influenza vaccines have been recommended for pregnant women by the CDC since 2012 and 2010, respectively. COVID-19 vaccines became available in December 2020; however, vaccination was not recommended for pregnant women by the CDC until August 2021 despite well documented risks of severe respiratory infections during pregnancy.
Objectives: To describe demographic characteristics and Tdap, influenza and COVID-19 vaccination patterns of pregnant women using a U.S. database of healthcare claims.
Methods: Healthcare claims data of female patients aged 12-55 with a live birth between 01Jan2016 and 30Sep2022 were analyzed. Conception was derived as 273 days prior to the live birth claim. Vaccines were identified from 3 months before conception through the date of birth. Timing of vaccination was categorized as 1) pre-quarantine (between 01Jan2016 and 29Feb2020), 2) quarantine (between 01Mar2020 and 30Nov2020), 3) post COVID-19 vaccine availability (between 01Dec2020 and 31Jun2021), and 4) post COVID-19 vaccine CDC recommendation (between 01Aug2021 and 30Sep2022).
Results: A total of 5,662,802 birth events across 4,824,113 distinct patients were included. There was a similar mean age at first occurrence of live birth (index date) across vaccination timing categories. The patient’s region at the live birth date was South (39.4%), Midwest (24.9%), West (17.4%) and Northeast (18.0%). Tdap vaccination occurred consistently in ~50% and influenza vaccination occurred consistently in ~30% of patients across all categories. COVID-19 vaccination occurred in 3.5% of patients during the post-COVID-19 vaccination availability category and 9.0% in post COVID-19-vaccine CDC recommendation category.
Conclusions: Despite CDC recommendations for Tdap and influenza, vaccination rates for pregnant women remained low, but were both consistent during each time period. Overall influenza rates are consistent with the U.S. general population vaccination rate, while Tdap rates in pregnant women are less than half. COVID-19 vaccination rates were considerably lower than for either Tdap or influenza during the post COVID-19 vaccine availability time period. Although the vaccination rates doubled in the time period following the CDC’s recommendation, it is still unsatisfactorily low to adequately protect mothers and infants.
