Schematic summarizing the general changes in circulating levels of FSH regulators, FSH secretory patterns, and posttranslational modifications of FSH during pubertal progression, menstrual cycle, and perimenopause transition in women (reviewed in Cumming, 1990; Padmanabhan et al., 2002; Ulloa-Aguirre et al., 2003; and Yding Andersen, 2017). CL, corpus luteum; DF, dominant follicle.