1 Women's Health Research Unit, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom Women's Health Research Unit, Barts and the London School of Medicine and Dentistry and, Multidisciplinary Evidence Synthesis Hub (MESH), Queen Mary University of London, London, United Kingdom Clinical Biostatistics Unit, Hospital Ramon y Cajal (IRYCIS) and CIBER Epidemiologia y Salud Publica (CIBERESP), Madrid, Spain.