Even with modern prenatal care, thousands of U.S. families each year experience the heartbreak of stillbirth, and a surprising number happen without warning. A study, published Monday in JAMA , analyzed nearly 2.8 million pregnancies and found that about 30% of stillbirths occurred with no clear medical cause or risk factor. Researchers from the Harvard T.H. Chan School of Public Health and Mass General Brigham said their findings highlight major disparities that continue to affect Black