A UK study reports that a history of irregular menstrual cycle was associated with higher risk for afib in women. A finding from the Vitamin D and Omega 3 Trial (VITAL) Rhythm Study reveals that when controlled for height and body size, women are at higher risk than men for afib, suggesting that biological sex and body size account for much of the protective effect of female sex. And as separately reported, early rhythm control is associated with lower risk for CV events as compared to usual care.