Menopausal Hormone Therapy: Who Can Take It Safely and Who Should Not?

Menopausal hormone therapy can be a reasonable option for many healthy women with bothersome hot flashes, night sweats or vaginal dryness, particularly when started near the time of menopause. It is not suitable for everyone. A history of breast cancer, blood clots, stroke, heart attack, liver disease or unexplained vaginal bleeding usually rules it out. This article explains who may take it, who should avoid it, the boxed warning, and which symptoms need urgent care.

Who may be a candidate for menopausal hormone therapy

Menopausal hormone therapy (often shortened to MHT or HRT) replaces some of the estrogen the ovaries make less of after menopause. MedlinePlus (NIH) describes hormone therapy for menopause as a treatment for symptoms such as hot flashes, night sweats and vaginal changes, and notes that it carries risks as well as benefits.

Clinicians often consider it for someone who:

• Has moderate to severe hot flashes or night sweats that disrupt sleep or daily life
• Is relatively close to the age of menopause, rather than many years past it
• Has no history of the conditions listed in the next section
• Has symptoms that did not improve enough with non-hormone options

The balance of benefit and risk is often described as more favorable for younger women who start soon after menopause, a question examined in a PubMed Central report from an expert panel on hormone therapy. It may be less favorable for women who start much later. Your age, time since your last period, personal and family history and preferences all shape the decision, so it is made with a clinician rather than from a checklist.

Who should not take hormone therapy

Estrogen-containing prescription labels list conditions in which hormone therapy is generally not advised. Tell your clinician if any of these apply so they can decide whether hormone therapy is appropriate:

• Breast cancer, now or in the past, or another cancer that responds to estrogen
• Unexplained vaginal bleeding that has not been evaluated
• A history of blood clots in the legs (deep vein thrombosis) or lungs (pulmonary embolism), or a known clotting disorder
• Stroke or heart attack, now or in the past
• Active liver disease
• Possible pregnancy

Some conditions call for extra care rather than a flat no. These include migraine with aura, high blood pressure, high triglycerides, gallbladder disease, endometriosis, fibroids, lupus and a strong family history of breast cancer. If you have migraine with aura, mention it, since clinicians weigh the stroke risk carefully when deciding whether and how to use estrogen.

The boxed warning on estrogen products

The approved labeling for estrogen products carries a boxed warning, and the PubMed Central report from an expert panel on hormone therapy discusses the evidence behind hormone therapy labeling. Estrogen taken with a progestogen has been associated with increased risks of breast cancer, cardiovascular disorders (such as stroke and blood clots) and probable dementia. Estrogen taken alone has been associated with endometrial cancer in women who still have a uterus, along with cardiovascular disorders and probable dementia. The label also advises that hormone therapy should not be used to prevent heart disease or dementia.

These warnings describe population-level risks. Your own risk depends on your age, health and the product. Read the label and the patient leaflet, and ask your prescriber or pharmacist about anything that applies to you. Do not change the dose, patch schedule or timing of a prescription on your own.

Estrogen alone versus estrogen plus a progestogen

If you still have a uterus, estrogen taken alone can thicken the uterine lining and may raise the risk of endometrial cancer. For that reason a progestogen (a progesterone-like medicine) is usually prescribed along with estrogen to protect the lining. If you have had a hysterectomy, estrogen alone is often used because there is no lining to protect.

The progestogen is not a free pass. Combination therapy has its own risk profile, including the breast cancer association noted in the boxed warning. Your clinician can explain how the type of progestogen and the schedule (cyclic or continuous) may affect bleeding patterns and risk.

Pills, patches, gels and vaginal estrogen

Hormone therapy comes in several forms, and the form can matter for safety.

• Oral estrogen passes through the liver and may increase clotting factors more than other forms.
• Transdermal estrogen (patch, gel or spray) is absorbed through the skin. A review in PubMed Central, Transdermal Hormonal Therapy in Menopause: Current Evidence and Personalized Approaches, discusses evidence that transdermal routes may carry a lower clotting risk than oral ones and may suit some people with added risk factors. Your clinician can tell you whether that applies to you.
• Low-dose vaginal estrogen (cream, tablet or ring) mainly treats vaginal dryness, discomfort with sex and some urinary symptoms. Because little reaches the bloodstream, it is often considered separately from systemic therapy. People with a history of hormone-sensitive cancer should still discuss it with their cancer team first.

Hormone therapy is also different from the hormones in a birth control pill. The clot question for contraceptives has its own article on this site, linked below.

Special situations

Early menopause or primary ovarian insufficiency

When the ovaries stop working normally before age 40, the situation differs from typical menopause. MedlinePlus (NIH) explains primary ovarian insufficiency, and hormone therapy is commonly discussed for these women to replace hormones their bodies would otherwise still be making, often until around the usual age of menopause. A specialist can guide the choice.

After a cancer diagnosis

Many cancers, including breast cancer, are affected by hormones, so hormone therapy is often avoided after them. Still, decisions depend on the cancer type, treatment and symptoms. A paper in PubMed Central, Using menopausal hormone therapy after a cancer diagnosis in Ireland, looks at how these decisions are approached. If you are a cancer survivor, your oncology team should be part of the conversation. MedlinePlus (NIH) provides background on breast cancer.

Bone health

Estrogen can help protect bone, but hormone therapy is not usually chosen only for that purpose. Other medicines are available for osteoporosis, and one of them is covered in the alendronate article linked below.

What hormone therapy does not do

Hormone therapy is aimed at symptoms. It is not recommended to prevent heart disease or dementia, and the boxed warning says so. Some people hope it will restore energy, weight or memory, but evidence for those uses is limited and results vary.

Non-hormone options exist for people who cannot or prefer not to use estrogen. They include certain antidepressants (SSRIs and SNRIs), gabapentin and, for some people, newer approved non-hormone medicines, each with its own cautions, along with cooling strategies and vaginal moisturizers and lubricants for vaginal symptoms. Your clinician can explain which fit your health history.

Before you start and while you take it

A visit about hormone therapy usually covers your symptoms, your medical and family history, blood pressure, and whether your breast and cervical screening are current. Clinicians combine your history, examination and any necessary testing; there is no single test that decides whether you are a candidate.

Tell your clinician about every medicine and supplement you take, including thyroid medicine and seizure medicine, since estrogen can change how thyroid medicine works and some seizure medicines can lower estrogen levels. Do not change those doses yourself. Bring up smoking, which adds to cardiovascular and clotting concerns.

Once you are on treatment, many clinicians review it regularly to check whether you still need it, whether the dose and form still fit, and whether new risk factors have developed. Bleeding after menopause, including spotting, deserves attention. MedlinePlus (NIH) explains vaginal bleeding and its many possible causes. Some irregular spotting is common in the first months of combination therapy, but ongoing or heavy bleeding should be evaluated.

Stopping hormone therapy

Some people stop after their symptoms settle, and others stay on treatment longer after discussing the pros and cons with their clinician. Symptoms can return after stopping, in some people. Ask your prescriber how they would like you to taper or stop, rather than deciding alone.

When to Seek Medical Care