Menopausal Hormone Therapy (MHT/HRT)

What it is

Estrogen ± progestogen replacement during and after menopause. Modern options include oral or transdermal estradiol with cyclical or continuous micronised progesterone in women with a uterus.

Why it matters for longevity

Estrogen withdrawal at menopause accelerates loss of bone density, unfavourable lipid shifts, increased visceral adiposity, and (in some women) cognitive symptoms and sleep disruption.

Timing hypothesis: started within ~10 years of menopause, MHT appears to reduce cardiovascular events and all-cause mortality. Started a decade or more later, the cardiovascular risk-benefit shifts.

Benefits

• Reliable relief of vasomotor symptoms.
• Protection against osteoporotic fracture.
• Likely cardiovascular benefit with early initiation.
• Possibly favourable cognitive trajectory if started early; less clear if started late.

Risks

• Venous thromboembolism (oral > transdermal).
• Stroke (oral; transdermal less so).
• Breast cancer with combined estrogen+progestogen, particularly with prolonged use; estrogen-only (in women without uterus) has more favourable breast-cancer signal.
• Endometrial cancer if unopposed estrogen in women with a uterus.

The WHI legacy

The Women’s Health Initiative (2002) initial results were widely mis-interpreted as showing MHT harm in symptomatic women. Reanalysis by timing-of-initiation and age strata has substantially modified recommendations; modern guidance favours individualised use, often transdermal estradiol, in symptomatic women without contraindications.

Related entries

Estrogen biomarker, Osteoporosis, Cardiovascular disease.