Examining the association between preterm birth and geographic disparities in the Maternal-Fetal Medicine physician workforce

Abstract

Maternal-Fetal Medicine (MFM) specialists disproportionately practice in metropolitan areas of the most populous states of the US. Prior regional data have suggested an improvement in preterm birth (PTB) rates with presence of MFM services within a community. We hypothesize that geographic disparity in the MFM physician workforce distribution nationally is associated with a higher rate of PTB in counties without MFM presence. Utilizing workforce data provided by the Society for Maternal-Fetal Medicine and county-level prematurity data from The March of Dimes, we mapped physician location in all 50 US states and Puerto Rico using R Studio software. Logistic regression analysis was utilized to estimate the odds of county PTB rates higher than the national average (10.2%, 2019 national data) by MFM physician location. The University of Iowa Institutional Review Board determined this study to be exempt and application was not required. Urban areas had the highest density of MFM physicians (purple circles in the figure) whereas less populous areas in the Midwest and western US had the lowest density. Out of the 2981 counties with PTB rates available, 9.7% (n = 289) had a practicing MFM physician. US counties without an MFM physician are more likely to have a PTB rate higher than the national average, OR 1.56 (1.22-1.99), when compared to a county with at least 1 MFM physician. In counties with no practicing MFM physician, those counties have a 56% increase in the odds of having PTB rates higher than the national average. Lack of proximate high-risk obstetric care is one of many disparities associated with PTB. The location of the MFM workforce has implications for both clinical care and health policy for maternal and neonatal care. These data suggest that attention should be directed toward where physicians practice and to increase access to care for at-risk pregnant people (i.e. outreach programs, telehealth).