Hormone Replacement Therapy (HRT)

Benefits, Risks, and Making an Informed Decision

Hormone replacement therapy (HRT)—also called menopausal hormone therapy—is the most effective treatment for menopause symptoms. However, it also carries risks that vary depending on your age, health history, and type of HRT used. Understanding both benefits and risks helps you make an informed decision with your healthcare provider.

What Is HRT?

Definition: Medications containing hormones (estrogen alone or estrogen plus progestin) to replace those your body no longer produces after menopause.

Purpose:

• Relieve menopause symptoms (primarily hot flashes, night sweats, vaginal dryness)
• Protect bones (reduce osteoporosis risk)
• Improve quality of life

Types of HRT

Estrogen-Only HRT

Who It’s For: Women who have had a hysterectomy (uterus removed). If you don’t have a uterus, you don’t need progestin.

Why Estrogen-Only: Estrogen alone stimulates uterine lining (endometrium), increasing endometrial cancer risk. Progestin protects the uterus. No uterus = no need for progestin.

Forms:

• Pills (oral estradiol)
• Patches (transdermal—changed once or twice weekly)
• Gels (applied to skin daily)
• Sprays
• Vaginal cream, ring, or tablet (for vaginal symptoms only—very little systemic absorption)

Combined Estrogen + Progestin HRT

Who It’s For: Women who still have their uterus. Must take progestin to protect uterine lining from estrogen’s effects.

Forms:

• Continuous combined: Estrogen + progestin daily (no periods)
• Cyclic/Sequential: Estrogen daily, progestin 12-14 days per month (causes monthly period)
• Combined pills, patches, or separate components

Progestins Used:

• Progesterone (bioidentical, micronized—Prometrium)
• Synthetic progestins (medroxyprogesterone acetate, norethindrone, drospirenone)
• Progestin IUD (Mirena) can provide uterine protection while using estrogen

Systemic vs Local

Systemic HRT:

• Estrogen absorbed throughout body
• Treats hot flashes, night sweats, bone loss, and vaginal symptoms
• Pills, patches, gels, sprays

Local (Vaginal) Estrogen:

• Inserted directly into vagina
• Treats vaginal dryness, painful sex, urinary symptoms
• Very little absorbed systemically (stays local)
• Much safer than systemic HRT
• Can be used even with history of breast cancer (discuss with oncologist)
• Does NOT treat hot flashes or protect bones

Key Point: If your only symptoms are vaginal dryness or urinary issues, use vaginal estrogen (safer). If you have hot flashes or night sweats, need systemic HRT.

Benefits of HRT

Symptom Relief

Hot Flashes and Night Sweats:

• Most effective treatment available
• Reduces hot flashes by 75-90%
• Effect usually seen within 2-4 weeks
• Dramatically improves quality of life

Vaginal Symptoms:

• Relieves vaginal dryness, irritation, painful sex
• Reverses vaginal atrophy
• Improves urinary symptoms
• Vaginal estrogen extremely effective

Sleep: By reducing night sweats, HRT dramatically improves sleep quality.

Mood: May improve mood, though not as effective as antidepressants for depression. Helps mood indirectly by improving sleep and reducing bothersome symptoms.

Bone Protection

Prevents Bone Loss:

• Estrogen is critical for maintaining bone density
• HRT prevents postmenopausal bone loss
• Reduces fracture risk by about 30-40%

Most Beneficial:

• Women who start HRT within 10 years of menopause
• Women with premature or early menopause
• Women at high fracture risk

Note: Bone protection lasts only while taking HRT. When stopped, bone loss resumes at menopause rate. Not generally used for osteoporosis treatment long-term (other medications available—see bone health pages).

Other Potential Benefits

Colorectal Cancer: Combined estrogen + progestin reduces colorectal cancer risk by about 30%. Estrogen-only may also reduce risk.

Type 2 Diabetes: May reduce risk when started early (under age 60).

Heart Health (If Started Early): Women who start HRT within 10 years of menopause or before age 60 may have reduced heart disease risk. “Timing hypothesis”—starting early may protect heart (see below).

Risks of HRT

Understanding risks is essential. The absolute risk increase for most complications is small, but varies based on your individual situation.

Breast Cancer

Combined Estrogen + Progestin:

• Increases breast cancer risk with prolonged use
• Risk increases after 3-5 years of use
• Absolute risk: About 1 additional breast cancer per 1,000 women per year of use after 5 years
• Risk returns to baseline within 3-5 years of stopping
• Progestin drives much of this risk

Estrogen-Only (After Hysterectomy):

• Does NOT increase breast cancer risk in most studies
• May even slightly decrease risk
• Much safer than combined HRT regarding breast cancer

Risk Factors That Increase Concern:

• Family history of breast cancer
• Personal history of breast cancer
• Dense breast tissue
• Previous abnormal breast biopsies
• BRCA mutations

Perspective:

• Obesity increases breast cancer risk more than HRT
• Alcohol consumption increases risk similarly to HRT
• Risk must be balanced against benefits and alternatives

Blood Clots (Venous Thromboembolism)

Increased Risk:

• About 2-3 times higher risk of blood clots with oral HRT
• Primarily in first 1-2 years of use
• Absolute risk: Low (about 1 additional blood clot per 1,000 women per year)

Transdermal (Patch/Gel) Is Safer:

• Does NOT increase blood clot risk (or minimal increase)
• First-pass through liver avoided
• Preferred for women at higher risk of blood clots

Risk Factors:

• History of blood clots
• Clotting disorders (Factor V Leiden, etc.)
• Obesity
• Immobility (long flights, surgery, bed rest)
• Smoking
• Age over 60

If High Risk: Use transdermal HRT or avoid HRT altogether.

Stroke

Increased Risk:

• Small increased risk with oral HRT, especially after age 60
• Absolute risk: About 1 additional stroke per 1,000 women per year (age-dependent)

Transdermal May Be Safer: Less clear than for blood clots, but transdermal may not increase stroke risk or increases it less.

Age Matters: Risk higher if starting HRT after age 60. Less concern if starting in 50s.

Risk Factors:

• Age over 60
• High blood pressure
• Diabetes
• Smoking
• Previous stroke or TIA
• Heart disease

Heart Disease

The Controversy and “Timing Hypothesis”:

If Started Early (Within 10 Years of Menopause or Age <60):

• May reduce heart disease risk
• Estrogen may protect blood vessels when started before significant atherosclerosis develops
• Most experts believe early HRT is cardiovascular neutral or beneficial

If Started Late (More Than 10 Years After Menopause or Age 60+):

• May increase heart disease risk
• Should not be started for heart disease prevention in older women
• If already taking HRT and tolerating well, continuing past 60 is reasonable

Bottom Line:

• Don’t start HRT primarily for heart protection
• Don’t start HRT after age 60
• Starting in 50s/early 60s for symptom management unlikely to increase heart risk

Ovarian Cancer (Uncertain)

Possible Small Increased Risk:

• Evidence mixed
• If risk exists, very small
• Less concern than breast cancer risk

Gallbladder Disease

Increased Risk:

• HRT increases gallstone risk
• May lead to need for gallbladder surgery

Dementia

WHI Memory Study:

• Combined HRT started after age 65 increased dementia risk
• Do NOT start HRT after 65
• No increased risk if started in 50s

Possible Benefit If Started Early: Some evidence that HRT started in 50s may reduce Alzheimer’s risk, but not conclusive.

Who Should NOT Use HRT (Contraindications)

Absolute Contraindications:

• Current or history of breast cancer (except vaginal estrogen—discuss with oncologist)
• Estrogen-sensitive cancers (endometrial cancer with residual disease)
• History of blood clots (DVT, PE)
• Active liver disease
• Unexplained vaginal bleeding (must be evaluated first)
• Known or suspected pregnancy
• History of stroke or heart attack
• Coronary heart disease

Relative Contraindications (Use Caution, May Use Transdermal):

• High risk of blood clots (obesity, clotting disorder)
• Migraines with aura
• Gallbladder disease
• High triglycerides
• Endometriosis, uterine fibroids (may worsen)

If You Have Contraindications: Non-hormonal options available (see symptoms page).

The “Right” Time to Start HRT

Best Time: Within 10 Years of Menopause or Before Age 60

• Greatest benefit-to-risk ratio
• Cardiovascular safety best
• “Window of opportunity” for heart protection

Can Start:

• During perimenopause if severe symptoms
• At menopause
• Within 10 years of menopause

Should NOT Start:

• More than 10 years after menopause
• After age 60 (unless already taking and tolerating well)
• Primarily for disease prevention (osteoporosis, heart disease) if no symptoms—other medications better

How Long to Use HRT

No Arbitrary Time Limit: Old recommendations (stop after 5 years) are outdated.

Current Guidance:

• Use lowest effective dose for shortest duration needed to manage symptoms
• Reassess annually with your provider
• Many women can stop after a few years when symptoms naturally improve
• Some women need HRT longer (10+ years)
• Benefits must outweigh risks at each decision point

If Symptoms Return After Stopping: Can restart if no contraindications developed.

Stopping HRT:

• Can stop abruptly or taper gradually
• Some women have symptom return (resume HRT or manage with non-hormonal options)
• Bone loss resumes when stopped

Special Situations:

Premature/Early Menopause (Before Age 45): Should continue HRT at least until age 51 (average menopause age) to protect bones and heart. Benefits clearly outweigh risks in this group.

Different Types and Doses

Estrogen Types:

• Estradiol: Bioidentical to human estrogen, most commonly prescribed
• Conjugated estrogens (Premarin): Derived from pregnant mare urine, used in WHI study
• Synthetic estrogens: Various forms

Doses:

• Start with lowest effective dose
• Standard dose: 1mg estradiol (oral) or 0.05mg (patch)
• Can adjust up or down based on symptom control and tolerability

Progestin Types:

• Micronized progesterone: Bioidentical, generally preferred (fewer side effects)
• Synthetic progestins: Medroxyprogesterone acetate (most studied), norethindrone, drospirenone, others

Custom Compounded “Bioidentical” HRT:

• NOT safer or more effective than FDA-approved HRT
• Not regulated (inconsistent doses, purity)
• More expensive
• Avoid—use FDA-approved HRT instead

Delivery Methods: Pills vs Transdermal

Oral (Pills):

• Convenient (take daily)
• Inexpensive
• Effective
• Disadvantage: First-pass liver metabolism increases clotting factors, may increase blood clot and stroke risk

Transdermal (Patches, Gels, Sprays):

• Avoids first-pass liver metabolism
• Lower risk of blood clots and stroke
• Steady hormone levels (no peaks and troughs)
• May have fewer side effects (headaches, nausea)
• Disadvantage: Skin irritation possible (patches), application daily/twice weekly

Which Is Better:

• Transdermal preferred if risk factors for blood clots or stroke
• Oral acceptable if no risk factors
• Both effective for symptoms

Side Effects

Common (Usually Resolve After 2-3 Months):

• Breast tenderness
• Nausea
• Headaches
• Bloating
• Mood changes
• Breakthrough bleeding

If Persistent:

• Adjust dose
• Change formulation (oral to patch, or vice versa)
• Change progestin type
• Try different schedule (cyclic vs continuous)

Most Women Tolerate Well: With proper selection and dose adjustment, most women have minimal side effects.

Monitoring While on HRT

Annual Visits:

• Breast exam
• Pelvic exam
• Blood pressure check
• Weight
• Reassess symptoms and need for continued HRT
• Discuss any new health conditions or concerns

Mammograms: Continue annual screening (more important than ever on HRT).

Other Tests as Needed:

• Endometrial biopsy if unexpected bleeding
• Lipid panel if cardiovascular risk factors
• Bone density (baseline and follow-up)

Alternatives to HRT

If HRT is not an option or you prefer to avoid it:

• Non-hormonal medications (SSRIs, gabapentin—see symptoms page)
• Vaginal estrogen (very safe even if can’t use systemic HRT)
• Lifestyle modifications
• Mind-body practices
• See managing symptoms page for comprehensive alternatives

Making Your Decision

Consider HRT If:

• Moderate to severe hot flashes, night sweats, or vaginal symptoms
• Symptoms significantly affect quality of life
• Within 10 years of menopause or under age 60
• No contraindications
• Lifestyle and non-hormonal options insufficient

Questions to Discuss with Your Provider:

• Am I a good candidate for HRT?
• Which type and dose would you recommend?
• What are my specific risks given my health history?
• How do benefits and risks compare to alternatives?
• How long would you recommend I use HRT?
• What monitoring do I need?

Shared Decision-Making: There’s no one-size-fits-all answer. Work with your provider to weigh your individual benefits and risks, considering your symptoms, health history, values, and preferences.

Myths and Facts

Myth: HRT causes cancer. Fact: Combined HRT slightly increases breast cancer risk with long-term use. Estrogen-only HRT does not. Risk is small and must be balanced against benefits. HRT reduces colorectal cancer risk.

Myth: All HRT is dangerous. Fact: For healthy women under 60 or within 10 years of menopause with bothersome symptoms, benefits generally outweigh risks.

Myth: You should stop HRT after 5 years. Fact: No arbitrary time limit. Use as long as benefits outweigh risks, reassessing regularly.

Myth: “Bioidentical” custom-compounded hormones are safer. Fact: Not true. FDA-approved HRT (including bioidentical forms like estradiol and micronized progesterone) is safer, more consistent, better studied.

Myth: HRT will make me gain weight. Fact: HRT does not cause weight gain. Women often gain weight during menopause regardless of HRT use due to aging, metabolic changes, and lifestyle. HRT may actually help prevent abdominal weight gain.

The Bottom Line

HRT Is Highly Effective: For moderate to severe menopause symptoms, HRT is by far the most effective treatment.

Risks Exist But Are Often Overstated: Media coverage has made many women unnecessarily fearful. For appropriate candidates, benefits typically outweigh risks.

Individualize: The decision depends on your symptoms, age, health history, and personal values. What’s right for one woman may not be right for another.

Timing Matters: Starting in your 50s or within 10 years of menopause is safest. Avoid starting after age 60.

You Don’t Have to Suffer: If menopause symptoms significantly affect your quality of life, HRT may be appropriate. Don’t let fear prevent you from considering effective treatment.

Discuss with Your Provider: Have an informed conversation weighing your specific benefits and risks. Make a decision you’re comfortable with.