Frank A Chervenak1, Laurence B McCullough2, Robert L Brent3. 1. Department of Obstetrics and Gynecology, Weill Medical College of Cornell University, New York, NY. 2. Center for Medical Ethics and Health Policy, Baylor College of Medicine, Houston, TX. 3. Department of Pediatrics, Sidney Kimmel College of Medicine of Thomas Jefferson University, Philadelphia, PA.