(246) Vaccination Use Among Pregnant Women 2016-2021: An Analysis Using Healthcare Claims

Publication Number: 577

Background: Over the last decade, immunizing pregnant women has increasingly been used to protect the mother, fetus, and infant from infectious diseases. Protection is provided through transfer of maternal antibodies via transplacental transport. Maternal antibodies serve as neonates’ primary source of protection during their first weeks of life when they are vulnerable. In the U.S., Tdap and influenza vaccines have been recommended for pregnant women since 2012 and 2010, respectively. COVID-19 vaccines became available in December 2020 but were not recommended by the CDC for pregnant women until August 2021.

Objectives: To describe demographic characteristics and Tdap, influenza and COVID-19 vaccination patterns of pregnant women using a US database of healthcare claims.

Methods: Healthcare claims data of female patients aged 12-55 with a live birth between 01Jan2016 and 31Oct2021 were analyzed in Komodo Health Sentinel System. 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 relevant to COVID-19 in the U.S. as 1) pre-quarantine (between 01Jan2016 and 29Feb2020), 2) mid-quarantine (between 01Mar2020 and 31Aug2020), 3) full quarantine (between 01Sept2020 and 30Nov2020), and 4) post COVID-19 vaccine availability (between 01Dec2020 and 31Oct2021).

Results: A total of 3,756,028 birth events across 3,306,300 distinct patients were included. Mean age at first occurrence of live birth (index date) was similar across vaccination timing categories. The patient’s region at the live birth date was South (36.3%), Midwest (26.1%), West (20%) and Northeast (17.2%). Tdap vaccination occurred consistently in ~50% and influenza vaccination occurred consistently in ~30% of patients in each vaccination timing category. COVID-19 vaccination occurred in 4.3% of patients during the post-COVID-19 vaccination availability time period.

Conclusions: Despite CDC recommendations for Tdap and influenza, vaccination rates for pregnant women remained low, but were both consistent during each COVID-19 quarantine timing period. Overall influenza vaccination rates are consistent with the U.S. general population vaccination rate, while Tdap vaccination 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. Delayed recommendation by the CDC may have contributed to the low rate of COVID-19 vaccination among pregnant women.