What Is Estrogen?
Estrogen is a naturally occurring female hormone.
There are 3 types of naturally occurring estrogens:
- Estradiol (E2) is largely produced by theca and granulosa cells of the ovary.
- It is the most prevalent type of estrogen found in women before menopause.
- Estrone (E1) is produced from estradiol in a reversible reaction and is also a product of the secondary conversion of androstenedione secreted by the adrenal cortex.
- Estriol (E3) is the estrogen the placenta secretes during pregnancy.
- Estriol is a secondary metabolite of estradiol and estrone.
- This form of estrogen is not secreted by the ovaries.
What Is Estrogen Used to Treat?
Estrogen therapy is used to treat:
- Vasomotor symptoms associated with menopause
- Hot flashes
- Studies have shown oral, transdermal, or vaginal hormone therapy reduce the severity of hot flashes by 65-90%
- Night sweats
- Sleep disturbances
- Hot flashes
- Osteoporosis
- Prevent bone loss
- Reduce the risk of fractures
- Genitourinary symptoms
- Vulvar burning or itching
- Vaginal dryness or discharge
- Vulvovaginal atrophy
- Painful sexual intercourse (dyspareunia) or post-coital spotting
- Recurrent urinary tract infections (UTIs)
- Pain or discomfort when urinating
- Urinary frequency or urgency
- Estrogen deficiency caused by hypogonadism
- Premature surgical menopause
- Premature ovarian insufficiency (POI)
Estrogen therapy is available in several forms:
- Oral
- Transdermal (applied to the skin)
- Patches
- Gels
- Sprays
- Lotions/creams
- Injectable
- Vaginal
- Suppositories
- Creams
- Rings
What Are the Benefits and Risks Estrogen Therapy?
The benefits of estrogen therapy include:
- Better sleep
- Maintenance of skin thickness, elasticity, and collagen
- Decreased risk of developing cataracts or open-angle glaucoma
- Improved balance and retention of balance
- Better maintenance of joint health
- May reduce the risk of developing colon cancer and type II diabetes
The risks of estrogen therapy include:
- Dry eyes
- Hearing loss
- Changes in sense of smell
- Cholelithiasis, cholecystitis
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References
Medscape Medical Reference