Fig. 3: Time series embedding and probability distribution for cycle length (all users, across groups).

Time series embedding (a) and probability distributions (b) of cycle length for the consistently not highly variable (teal) and consistently highly variable (orange) groups. a The cycle lengths of three consecutive randomly sampled cycles from each user in the cohort are plotted on the x, y, and z axes. Each consistently not highly variable user is represented by a teal point, and each consistently highly variable user by an orange point. It is visually evident that the teal cluster of users occupies a tighter region of the space around the x = y = z line, with the orange cluster fanning outward. b The cycle length probability distributions of the cohort, where we note that the orange group’s distribution has a much wider spread and is less peaked than the teal group. Cycle lengths are more heterogeneous or widely distributed for the orange group, confirming that the consistently highly variable group represents those with more fluctuation in cycle length. The cumulative distributions per group differ significantly (as per a two-sample Kolmogorov–Smirnov test).