Women's hormone levels can change throughout the day and throughout their life. A woman's estrogen and progesterone levels are both regulated by her menstrual cycle, so it's important to know how to interpret them. If a woman has a low estrogen level, it could be a sign of an underactive or absent ovaries or a pituitary disorder. If a woman has a high estrogen level, it could be a sign of an overactive ovaries or a tumor. A high progesterone level could be a sign of an overactive thyroid or an underactive ovaries.