Hormonal profiles (realigned data) from ovulatory cycles (A, estradiol; B, progesterone; C, LH; D, FSH) of women enrolled in the BioCycle Study by cycle length category, short (<26 d), normal (26 to 35 d), long (>35 d). Serum measurements were collected at eight cycle visits timed to menstrual cycle phase using fertility monitors corresponding to the second day of menstruation, mid follicular, late follicular, 3 d around expected ovulation, and early, mid, and late luteal phase (approximately corresponding to d 2, 7, 12, 13, 14, 18, 22, and 27 of a standardized 28-d cycle), with collection dates adjusted for cycle length. *, Pairwise comparison for short vs. normal P < 0.05. †, Pairwise comparison for short vs. long P < 0.05. ‡, Pairwise comparison for normal vs. long P < 0.05.