Thirty-six-year-old Lindsay Doherty collapsed at the end of Sunday's 13.1-mile (21.1-kilometer) Scranton Half Marathon.
According to the Allentown Morning Call, the Lackawanna County coroner ruled Doherty died from intra-abdominal bleeding caused by a hemorrhage.
The Roman Catholic Diocese of Scranton says Doherty worked in its development office, raising money for Catholic education. A special prayer service was scheduled for Monday night.
The Scranton resident had run the half marathon the previous year.
Medical workers, including two emergency room physicians, worked to resuscitate Doherty at the race before she was taken to the hospital.
Report a typo to the ABC13 staff