US
U.S. Department of Health and Human Services, Office of Inspector General
Published June 2026

Inaccurate Medicaid Managed Care Network Lists May Compromise State Oversight of Access to Maternal Health Care

Learn how the AI-generated research projects were created

Overall Conclusion

We found that the network lists from Centene, Elevance, and UnitedHealthcare Medicaid plans in five States contained inaccuracies—potential ghost providers who reported not being in-network, incorrect contact information, and discrepancies with online provider directories—that may compromise State oversight of access to maternal health care.

Source Document

Audit Scope

Scope included Centene, Elevance, and UnitedHealthcare Medicaid managed care plans in five States (Louisiana, Missouri, Nevada, New Jersey, Washington); data current as of January 2025; random sample of 453 maternal health providers (OB/GYN physicians and certified nurse-midwives) across the five States; online directories checked; provider surveys conducted June–July 2025; analyses compared network lists to online directories and survey responses.

Key Findings Summary

1

Network lists from Centene, Elevance, and UnitedHealthcare Medicaid managed care plans in five States contained ghost providers—providers who should not be listed because they were not an in-network provider with the plan.

2

Medicaid managed care plans did not list any accurate phone numbers for over one-quarter of maternal health providers.

3

Almost half of maternal health providers in Medicaid managed care plans’ network lists did not appear in plans’ online provider directories.

AI-Assisted

Generated by gpt-5-nano

AI Scope Summary

This audit assessed the accuracy of Medicaid managed care provider network lists and online directories for maternal health providers across five States, focusing on OB/GYNs and certified nurse-midwives, with a sample-based approach and provider surveys. The findings show substantial ghost providers, missing phone numbers, and discrepancies with online directories, underscoring the need for CMS-State collaboration to improve data accuracy and oversight.

AI-Generated Insight

This OIG report identifies significant data quality issues in Medicaid managed care provider network lists, including ghost providers and missing/different phone numbers, which can undermine States’ ability to oversee network adequacy for maternal health care. The report recommends CMS collaborate with States to improve provider data accuracy and to support accountability measures for plans.

Audit Objectives

1

To evaluate the accuracy of information about maternal health providers in the network lists that Medicaid managed care plans send to States for oversight.

Audit Findings (3)

1

Network lists from Centene, Elevance, and UnitedHealthcare Medicaid managed care plans in five States contained ghost providers—providers who should not be listed because they were not an in-network provider with the plan.

2

Medicaid managed care plans did not list any accurate phone numbers for over one-quarter of maternal health providers.

3

Almost half of maternal health providers in Medicaid managed care plans’ network lists did not appear in plans’ online provider directories.

Recommendations (2)

1

CMS should work with States to improve the accuracy of the provider data they use to evaluate the adequacy of networks in Medicaid managed care.

2

CMS should take steps to support States in holding Medicaid managed care plans accountable for the accuracy of the network lists used for assessing network adequacy.