Rep. Underwood is a registered nurse and co-founder and co-chair of the Black Maternal Health Caucus, which addresses America's Black Maternal Health crisis in Congress and advances policy solutions to improve maternal health outcomes and end disparities. Rep. Underwood is Co-Chair of the House Democratic Policy and Communications Committee and serves on the House Committee on Appropriations.

Prior to her election to Congress, she served as a Senior Advisor at the U.S. Department of Health and Human Services (HHS), helping communities across the country prevent, prepare for, and respond to disasters, bioterror threats, and public health emergencies. As a career public servant at HHS, she also helped implement the Affordable Care Act, broadening access for those on Medicare, improving health care quality, and reforming private insurance. Rep. Underwood has taught future nurse practitioners through Georgetown University's online master's program and worked with a Medicaid plan in Chicago to ensure it provided high-quality, cost-efficient care.

She is a graduate of the University of Michigan and Johns Hopkins University, and a lifelong Girl Scout. Rep. Underwood resides in Naperville, Illinois.