Theory 28/Menstrual cycle/Onset phase
Onset Is Follicle Recruitment
The claim
A cycle begins when the ratio of FSH to follicular reserve exceeds a threshold, so the same hormone level produces different recruitment at different reserves.
01Mechanism
Recruitment requires FSH to exceed inhibition from the cohort; the ratio determines how many follicles start.
02Prediction
Recruitment should track the ratio.
03Refutation
Recruitment tracking FSH alone would remove reserve.