Canadian Woman — St. Marguerite d'Youville

In 1978, a Canadian woman with acute myelogenous leukemia (AML) suffered a relapse. At that time, leukemia relapse was considered incurable; median survival even with treatment was about 18 months. Following prayers for Marguerite d'Youville's intercession, she went into a sudden second remission that proved lasting. In 1987, the Vatican submitted the patient's bone marrow slides to Dr. Jacalyn Duffin—a secular, atheist hematologist at Queen's University—without revealing the case details. Duffin examined the slides blindly and identified characteristic Auer rods confirming the AML diagnosis. She concluded that the recovery was entirely scientifically inexplicable. Duffin later wrote Medical Miracles (Oxford, 2008), analyzing the Vatican's medical archives. d'Youville was canonized December 9, 1990—the first native-born Canadian saint.

Dr. Duffin is a secular, atheist physician—her independent conclusion adds credibility. The Vatican's blind submission of slides eliminates bias; she did not know the case details when examining. AML relapse in the 1970s had no cure. Duffin examined 1,400+ Vatican canonization cases and wrote the definitive academic study. She has stated the patient remained alive decades later and she still could not explain the recovery. The evidence stands on secular medical review, not ecclesiastical authority.