What Can Cause Low Estrogen Levels?
Menopause – the menopause and the period before it, known as the perimenopause, brings about hormonal changes in females. Decreasing levels of oestrogen during the menopause is associated with the development of hot flushes. However, hot flushes are also likely to occur in women who have a high body mass index (BMI).
Too much exercise – increased exercise can cause low estrogen levels. There is some evidence which suggests that increased physical activity in premenopausal women can result in a reduced risk of breast cancer due to the decreased level of oestrogen.
Being underweight – being underweight or having anorexia nervosa can have serious implications for your health. Anorexia in females can cause low estrogen levels and may result in a later onset of menstruation or the absence of periods. These factors are also determinants of low bone mass density which can put you at an increased risk of fractures and osteoporosis.
Premature ovarian failure – this is also known as premature menopause and usually occurs before the age of 40. Early menopause occurs at or before the age of 45, but both can occur naturally or be induced through factors such as medical treatment.
When premature or early menopause occurs, the ovaries stop making specific hormones particularly estrogen. Premature ovarian failure often runs in families although this is not always the case.
Turner Syndrome – this is a genetic disorder which affects females, around 1 in 2000 baby girls. There is a wide range of symptoms associated with Turner Syndrome, including:
Turner Syndrome can affect the ovaries. They are female reproductive organs which produce sex hormones and trigger the start of a girl’s periods. However, 9/10 of girls with Turner Syndrome do not produce enough of these sex hormones including estrogen. This means:
- They may need hormone replacement therapy (HRT) as they may not develop sexually without it
- They may not start their periods naturally
- They are likely to be infertile
Most girls with Turner Syndrome will begin HRT between the ages of 10 and 12 and then progesterone therapy around 3 years later to induce their periods.
Cancer treatment – hormonal therapy with or without chemotherapy is often used as a treatment for breast cancer. However, it can suppress the release of estrogen and in turn, bring on the menopause.
The Menstrual Cycle – during the menstrual cycle, estrogen levels naturally fluctuate. On day one both estrogen and progesterone levels are low which tells the pituitary gland to produce follicle stimulating hormone (FSH). FSH starts the production of a follicle – a fluid-filled sac which contains an egg in the ovary.
The follicle produces estrogen and levels rise which prepares the uterus for pregnancy. Between days 12 and 14, ovulation usually occurs and the high estrogen levels cause a sharp rise in Luteinizing Hormone (LH) which causes the egg to be released from the follicle.
The ruptured follicle also called the corpus luteum secretes both progesterone and estrogen to continue the preparation of the uterus for pregnancy. If the egg is not fertilised then the levels of estrogen and progesterone drop. On day 28, a bleed will take place.
The Pill – a contraceptive pill is a synthetic form of progesterone and estrogen, the female sex hormones. The pill stops ovulation from occurring by keeping the hormone levels consistent. If there isn’t a peak in estrogen then the ovary doesn’t release an egg, which prevents pregnancy.