Fig. 1: Diagram of included participants.

Diagram of participant exclusion criteria illustrating the number of participants excluding at each step of data refinement. Two pathways are shown illustrating the naturally cycling cohort on the left side and the birth control pills cohort on the right side. In total 23,395 participants were assessed for eligibility; 9968 participants were included in the naturally cycling cohort and 1661 participants were included in the birth control pill cohort.