Estrogen levels typically drop as women enter menopause, which commonly occurs between age 45 and 55. Low estrogen levels can occur at any age, however, and may be related to autoimmune disease, surgical removal of ovaries or premature ovarian failure, among other causes. Many symptoms are related to low estrogen levels and menopause.
Menstrual Symptoms
The most common sign of low estrogen levels is a lack of menstrual periods, also known as amenorrhea. Amenorrhea occurs when estrogen levels are low because the uterine lining isn't thickening under the influence of estrogen. During perimenopause, a period of 2 to 8 years leading up to menopause, periods may become irregular and scant if estrogen levels are low.
Hot Flashes
Hot flashes often occur when estrogen levels drop; they occur in as many as three quarters of all menopausal women, according to the Merck Manual. Hot flashes, which last from 30 seconds to 5 minutes, cause sudden flushing and perspiration. Hot flashes during the night cause night sweats, according to Merck, and can lead to problems sleeping. Heart palpitations, headaches and dizziness may accompany hot flashes, the University of Maryland Medical Center says.
Vaginal and Urinary Symptoms
The lack of estrogen directly affects vaginal and external genitalia tissues, which thin, shrink and atrophy without the influence of estrogen. Lubrication decreases, making intercourse uncomfortable. Vaginitis, or vaginal infection, becomes more common. The urinary tract also changes with lower levels of estrogen, with the urethra becoming shorter and thinner, making it easier for bacteria to enter the urinary tract and cause infection.
Bone Symptoms
Bone becomes thinner and bone density decreases when estrogen levels decrease, because estrogen helps strengthen bone. The risk of osteoporosis and bone fractures increases. Bone density drops as much as 3 to 5 percent in the first two years of menopause, and 1 to 2 percent thereafter, according to the Merck Manual.
Skin Symptoms
Skin becomes thinner when estrogen levels fall, because collagen, which strengthens skin, and elastin, which increases skin elasticity, decrease when estrogen decreases. Skin is dryer, less elastic and more prone to injury when estrogen levels are low.
Mental Symptoms
Changes in mental status may accompany low estrogen levels, although the Merck Manual states there isn't conclusive proof that these changes are tied to low estrogen. Menopausal women may have memory loss, depression, irritability, anxiety, trouble concentrating and mood swings; these symptoms usually occur in conjunction with sleeping difficulties, the University of Maryland Medical Center states.
