University of Waterloo Mar 4 2026 High blood pressure, or hypertension, affects more than one billion people worldwide and is a leading cause of heart disease and stroke. For decades, researchers have observed that premenopausal women are less likely to develop high blood pressure than men or postmenopausal women. Researchers have known for years that estrogen is the deciding factor, but exactly how it offers this protection has remained unclear.  New research from the University of Waterloo