Nine estrogen and progesterone measurements are taken throughout the cycle to characterize the follicular, ovulatory, and luteal phases.
The expected pattern of hormones is:
- Relatively low estrogen levels early in the cycle
- A surge of estrogen around ovulation
- Modest estrogen levels in the latter third of the cycle (the luteal phase)
- Progesterone levels stay relatively low until after ovulation
- After ovulation progesterone levels ideally increase (>10-fold) and then drop back down at the end of the cycle