Postpartum Measles, Varicella, and Rubella Vaccination Rates in Serologically Non-Immune Mothers with Public Insurance at an Urban Tertiary Care Center.

The postpartum period provides an opportunity to improve maternal and infant health, including identifying risks and completing immunization series. Research on completion of varicella and measles, mumps, and rubella (MMR) vaccine series among postpartum mothers is limited. This study examined data from mothers with public health insurance who received prenatal and postpartum care at the Mount Sinai Health System between January 1, 2021, and June 27, 2022. Two hundred and fifty-four (254; 11.9%) lacked immunity to at least one of these viruses: 104 to measles, 53 to rubella, and 137 to varicella. Forty-four percent (44.5%) and 52.7% initiated varicella and MMR series, respectively, during their immediate postpartum care. However, only 19% and 3.8% completed varicella and MMR series during their six-week postpartum visit, respectively. These findings underscore low rates of complete vaccination for measles, rubella, and varicella among serologically non-immune postpartum mothers with public health insurance.