Defunding Sexual Healthcare: A Topological Investigation of Resource Accessibility

Government actions, such as the Medina v. Planned Parenthood South Atlantic Supreme Court ruling and the passage of the Big Beautiful Bill Act, have aimed to restrict or prohibit Medicaid funding for Planned Parenthood Healthcare Centers (PPHCs) at both the state and national levels. These funding cuts are particularly harmful in states like California, which has a large population of Medicaid users. This analysis focuses on the distribution of Planned Parenthood clinics and Federally Qualified Health Centers (FQHCs), which offer essential reproductive healthcare services including, but not limited to, abortions, birth control, HIV services, pregnancy testing and planning, STD testing and treatment, and cancer screenings. While expanded funding for FQHCs has been proposed as a solution, it fails to address the locational accessibility of Medicaid-funded health centers that provide sexual and reproductive care. To assess this issue, we analyze the proximity of data points representing California’s PPHC and FQHC locations. Topological Data Analysis (TDA)-an approach that examines the shape and structure of data – is used to detect disparities in reproductive and sexual healthcare coverage. To conduct data collection and visualization, we utilize R and Python. We apply an n-closest neighbor algorithm to examine distances between facilities and assess changes in travel time required to reach healthcare sites. We apply persistent homology to analyze current gaps across multiple scales in healthcare coverage and compare them to potential future gaps. Our findings aim to identify areas where access to care is most vulnerable and demonstrate how TDA can be used to analyze spatial inequalities in public health.

💡 Research Summary

This paper presents a novel application of Topological Data Analysis (TDA) to assess the potential impact of defunding policies on spatial accessibility to sexual and reproductive healthcare. The study is motivated by recent U.S. government actions, such as the Medina v. Planned Parenthood South Atlantic Supreme Court ruling, which aim to restrict Medicaid funding for Planned Parenthood Health Centers (PPHCs). While expanding funding for Federally Qualified Health Centers (FQHCs) is often proposed as an alternative, the authors argue this fails to address the critical issue of locational accessibility for Medicaid beneficiaries.

Focusing on California due to its large Medicaid population, the research analyzes the geographic distribution of PPHCs and FQHCs. The methodological innovation lies in using TDA, specifically Persistent Homology (PH), to move beyond simple distance measurements. Instead of Euclidean distance, the authors construct a custom distance metric based on realistic travel time, which serves as a proxy for access burden. This metric integrates estimated travel times (car, public transit, walking) between facilities obtained via the Google Maps API, weighted by county-level car ownership rates from the California DMV. This approach acknowledges that access is not just about miles but about the time and means required for transportation.

The core analysis involves building two Vietoris-Rips (VR) filtrations on point clouds representing healthcare facilities. The first point cloud includes all PPHC and FQHC locations, modeling the current state of access. The second includes only FQHCs, modeling a hypothetical future where PPHCs are inaccessible to Medicaid patients. As the filtration parameter (radius) increases, simplicial complexes (networks of points, edges, and triangles) form. Applying PH allows the researchers to track the “birth” and “death” of topological features, particularly 1-dimensional holes (loops). A persistent hole that lasts over a wide range of radii indicates a significant geographic gap in coverage—an area surrounded by healthcare facilities but with none inside.

By comparing the persistence diagrams from the two filtrations, the study identifies regions where the loss of PPHCs would create new or significantly enlarge existing coverage gaps. The results visually and quantitatively demonstrate that the absence of PPHCs would lead to more extensive and persistent access deserts in certain areas, suggesting that simply funding more FQHCs may not adequately replace the spatial coverage provided by the PPHC network.

In conclusion, the paper successfully demonstrates that TDA and PH are powerful tools for analyzing spatial inequalities in public health resource distribution. It provides a quantitative framework for policymakers to anticipate the geographic consequences of funding changes, emphasizing that resource allocation must consider not just the number of facilities, but the shape and structure of the access network they form. The work highlights the vulnerability of specific regions to policy shifts and underscores the importance of spatial equity in healthcare planning.