The risk of death for people who donate a kidney for transplantation -; already small a decade ago -; has dropped by more than half since then, a new study shows. Each year, roughly 6,000 Americans volunteer to donate a kidney, according to the Organ Procurement and Transplantation Network. Before undergoing the procedure, donors are informed of the potential risks, including death.

Based on data from 1995 through 2009, experts had originally predicted that about three of every 10,000 donors were likely to die within three months of the procedure. The authors of the new study argue that advances in surgical techniques, donor selection, and postoperative care have since rendered that estimate out of date. Analyzing three decades of medical records representing 164,593 kidney donors from across the country, a team led by researchers at NYU Langone Health found that by 2022, fewer than one death occurred for every 10,000 donations.

That translates into 36 deaths in total over 30 years. "While we had always understood that kidney donation is safe, our findings suggest that mortality among donors is extremely rare, and the procedure is safer than ever before," said study lead author Allan Massie, PhD. Massie is director of the Center for Surgical and Transplant Applied Research (C-STAR) Quantitative Core at NYU Grossman School of Medicine, where he is also a faculty member in the Departments of Surgery and Population Health.

The results further showed that while their overall risk.