Factors impacting rate of CH clonal expansion. Participants in the Women’s Health Initiative were screened for CH at baseline and after 15 years using sequencing with minimal VAF of 0.5%. Rate of expansion correlated with increased risk of cytopenia, leukemia, and all-cause mortality. Important determinants of expansion included initial clone size, gene mutated, germ line polymorphisms, TL, and IL-6 signaling.