Table 1.

Inclusion and exclusion criteria for regular cycles.

Inclusion Criteria

Exclusion Criteria

Regularly menstruating participants aged 18–45 Consistent cycle lengths between 24–38 days Knowledge of previous 3 cycle lengths Negative pregnancy test at the beginning and at the end of each cycle Able to travel to clinic in Calgary for regular ultrasounds during the study period

Anovulation in the last 3 cycles Currently, or in the previous 3 months, on medications that are known to impair or stimulate ovulation (e.g., oral contraceptives, ovulation stimulants, etc.) Known conditions that impair ovulation or fertility: ▪ polycystic ovarian syndrome ▪ endometriosis ▪ pelvic inflammatory disease in the last year ▪ pituitary adenoma ▪ breastfeeding Previous surgeries impacting the menstrual cycle: ▪ hysterectomy ▪ bilateral oophorectomy Currently pregnant