Estrogen levels vary with no single level considered typical, according to WebMD. Estradiol, the primary estrogen hormone in women, fluctuates based on menstrual cycle and menopausal status.
Reference values for estrogen range from 27 to 123 picograms per milliliter in the midfollicular phase, 96 to 436 picograms per milliliter during the periovulatory phase, 49 to 294 picograms per milliliter in the midluteal phase, and 0 to 40 picograms per milliliter postmenopausal, as reported by Medscape.
At the start of each menstrual cycle, estrogen is released from the ovaries, with levels peaking just prior to ovulation and then falling quickly after, as stated by WebMD. After menopause, estrogen levels drop to under 10 picograms per milliliter, as reported by Medscape. Other factors that can effect estrogen levels include pregnancy, tumors in the ovaries and certain drugs such as steroid medications, according to WebMD.