Menopause, Osteoporosis, and Hormone Therapy

About 50% of people who have been through menopause develop osteoporosis. Bone loss increases rapidly following menopause, significantly increasing the risk of osteoporosis and related fractures.

One way to treat or prevent osteoporosis in postmenopausal people is with hormone therapy. This article discusses how hormone therapy can help, how it is used, and the risks associated with it.

Menopause and Bone Health

Osteoporosis is more common in people who have been through menopause, the time when a woman is without a period for 12 consecutive months. A woman's bone mass is greatest at around age 25 to 30 before it begins to decline.

(Note that for the purposes of this article, "woman" refers to a person assigned female at birth. When health authorities or research are cited, the terms for gender or sex from the source are used.)

Estrogen (a sex hormone) slows the natural breakdown of bones, protecting them from weakening. During perimenopause (the beginning of menopausal changes), estrogen levels fluctuate. They then drop after menopause. With a lack of estrogen, bone loss occurs significantly faster, increasing the risk of osteoporosis and fractures.

This bone loss occurs in two phases. The first phase starts with menopause and lasts about four to eight years. Bone loss in this phase is more rapid and is caused by a drop in estrogen.

The second phase is persistent, slower bone loss. It is age-related and affects all sexes.

What Is Menopausal Hormone Therapy?

Menopausal hormone therapy (MHT), formerly referred to as hormone replacement therapy (HRT), is the supplementation of estrogen, with or without the hormone progesterone, to the lowest level needed to prevent bone loss.

Types of Hormone Therapy

MHT comes in two basic types, as follows:

• Estrogen-only therapy (ET): This therapy is prescribed for people who have had a hysterectomy (removal of the uterus).
• Estrogen plus progesterone therapy (EPT): Progesterone is given along with estrogen to protect against the risk of uterine (endometrial) cancer as estrogen therapy increases this risk.

MHT can be taken systemically, meaning it will reach all parts of the body through the bloodstream. This is the form that helps treat and prevent osteoporosis, along with other symptoms of menopause. Systemic methods include:

• Oral tablets
• Skin patch
• Gel
• Emulsion
• Spray
• Injection
  

Vaginal symptoms can be treated with localized application, using the following:

• Cream
• Ring
• Tablet

There are also medications that affect hormones which may be used on their own, or in some cases with MHT, to treat osteoporosis, including:

• Selective estrogen modulators (SERMs): These drugs affect estrogen receptors, blocking the estrogen effect in some sites and promoting it in other sites. They work like estrogen in bones to help increase bone mass density, primarily in the spine. Examples of SERMs include Evista (raloxifene) and Conbriza or Vivant (bazedoxifene).
• Tibolone: This synthetic steroid is not available in the United States but is used elsewhere in the world. It has estrogenic, progestogenic, and androgenic effects. It suppresses bone turnover, leading to positive effects on bone mineral density and lowered fracture risk.
  

MHT for Osteoporosis Prevention and Treatment

Whether to use MHT as an osteoporosis treatment and prevention depends on a number of factors, including other symptoms you are experiencing, characteristics such as your age, how long it has been since you went through menopause, and the risk-benefit balance.

Who’s a Good Candidate?

MHT is typically used to treat and prevent osteoporosis in people who have been through menopause and are also:

• Are at risk of fracture
• Are experiencing symptoms such as hot flashes and night sweats (not always a requirement)
• Are younger than age 60
• Went through menopause within the past 10 years
• Have not had breast cancer and are not at high risk for breast cancer

Hormone therapy should be avoided if you:

• May be pregnant
• Have vaginal bleeding
• Have had certain cancers
• Have had a heart attack or stroke
• Have had blood clots
• Have liver disease
  

Benefits

Particularly when used soon after the start of menopause, MHT can:

• Prevent bone loss (bone loss resumes once MHT is stopped)
• Increase bone density (about 5% in two years, according to some studies)
• Reduce risk of spinal fractures
• Reduce incidence of all osteoporosis-related fractures, including hip fractures
  
• Relieve other symptoms related to menopause, such as vaginal dryness, hot flashes, sleep problems, and night sweats
  

Risks and Side Effects

Hormone therapy is not for everyone. For some people, the side effects and risks may outweigh the benefits.

Side effects can include:

• Breast tenderness
• Weight gain
• Skin irritation
• Headaches
• Depression
• Premenstrual syndrome (PMS)
• Return of menstrual bleeding

Side effects may be improved or eliminated by changing dosages or types (such as pills vs. patches). Talk to your healthcare provider if you are experiencing side effects.

MHT can also increase the risk of the following:

• Breast cancer
• Cardiovascular disease and heart attack
• Stroke
• Venous thromboembolism (blood clots in veins)
• Endometrial/uterine cancer (in people with a uterus who take estrogen without progesterone)
• Gallbladder disease

To help mitigate these risks, MHT should be taken at the lowest effective dose and for the shortest time necessary, as determined by your healthcare provider.

Another downside of MHT is that after MHT is stopped, the protection it offers to bone mineral density begins to decline and at an unpredictable rate. You may still have some degree of protection against fracture, but other medications or treatment may be needed to protect your bones.

Talking to Your Healthcare Provider About Hormone Therapy

The decision process regarding starting hormone therapy should include a discussion with your healthcare provider about your personal risks and benefits. While there are overall risk trends to watch for, having a discussion with your healthcare provider will provide you with a personal outlook by taking into consideration your symptoms and medical history. This discussion should also include options other than hormone therapy that are available to you.

Some questions to ask your health care provider include:

• What is my level of bone density?
• Am I at high risk for fractures?
• Is treatment necessary?
• Does treatment need to start now, or can it be held off?
• What are the benefits, side effects, and risks of this treatment?
• What other treatments are available?
• Should I be taking supplements such as calcium and vitamin D?
• Should I see other specialists such as an endocrinologist?
• What else can I do to lower my risk of fractures?
• How often should I come back for follow-up?
  

Summary

The drop in estrogen that occurs at menopause causes an increase in bone loss and decreased bone density. This can lead to osteoporosis and make fractures more likely to occur.

Hormone therapy is one way to help counter this bone loss and reduce the risk of fracture. MHT can be estrogen only, for people whose uterus has been removed, or estrogen and progesterone, for people with an intact uterus.

Other medications are also available, such as raloxifene, and bazedoxifene. MHT is most beneficial when started close to the onset of menopause.

Taking hormone therapy comes with side effects and increases the risk of some health conditions, such as breast cancer and cardiovascular disease. A discussion of these risks vs. benefits is necessary before starting MHT.

If you have been through menopause, talk to your healthcare provider about your risk of osteoporosis and fracture. MHT may be one way for you to help maintain bone health.