Every month after menstruation the body begins to rebuild oestrogen levels in the form of oestradiol (the active form of oestrogen). Some oestradiol is converted to a weaker oestrogen called oestrone. Oestradiol and oestrone are then secreted into the bloodstream and travel to oestrogen sensitive cells to stimulate cell growth. Peak oestrogen levels are found just prior to ovulation and then falls just before menstruation begins.
Oestrogens are made from progesterone and/ or androgens in the ovarian cells. After menopause, oestrogens are converted from the adrenal producing androgens, primarily in body fat. Oestrogen and progesterone are both antagonistic and yet sensitise receptors for the other. Progesterone has a balancing effect on excessive oestrogen.
Sources of oestrogen
Oestrogen exhibits sustaining effects on the female reproductive system, it is a hormone which is produced in the ovaries and signalled by the pituitary gland. Oestrogen is the dominant female hormone and its functions are:
Many female health problems and symptoms occur due to hormone imbalance, typically oestrogen dominance. Oestrogen dominance or progesterone deficiency occurs in a woman where there is a high oestrogen to progesterone ratio. Symptoms of this hormonal imbalance are many and include: