Pg/E2 Ratio

A high ratio occurs when Pg is high relative to E2. This is most common with supplementation and describes progesterone dominance. When this occurs, a patient may complain of symptoms of estrogen deficiency resuming after previous successful treatment as estrogen receptors are down-regulated by excessive progesterone. In general, either increasing estradiol and/or decreasing progesterone are appropriate. This commonly occurs in menopause after a woman has been using progesterone successfully in perimenopause and her estrogen levels finally start to decrease as menopause is reached.

A low ratio occurs when Pg is low relative to E2. This describes the classic situation of estrogen dominance. In general, either decreasing estrogen and/or increasing progesterone are appropriate. Women who are postmenopausal are generally in this group.

This ratio is helpful when both E2 and Pg are within range, yet the patient continues to have symptoms. It is not expected to be normal or used clinically when either E2 and/or Pg are outside of their expected ranges or if the patient does not have clinical symptoms.