HRT for Women: A Plain Guide to Hormone Replacement Therapy in Perimenopause and Menopause

Few medical topics have generated more confusion, fear, and conflicting advice for women than hormone replacement therapy. The Women's Health Initiative study in 2002 triggered a mass withdrawal from HRT that affected millions of women who were suffering significantly — and whose suffering was largely unnecessary. It has taken two decades to begin correcting that damage.

What follows is a plain account of what HRT is, what the current evidence says, what the risks actually look like, and how to think about whether it is right for you.

What HRT Is

Hormone replacement therapy replaces the oestrogen (and in women with a uterus, progesterone) that the ovaries stop producing in sufficient quantities during perimenopause and menopause. The goal is to relieve symptoms caused by this decline and, in some cases, to protect long-term health.

Symptoms that HRT addresses most effectively:

• Hot flashes and night sweats (vasomotor symptoms) — HRT is the most effective treatment available
• Sleep disruption related to vasomotor symptoms and progesterone decline
• Vaginal dryness and urogenital symptoms
• Mood instability and anxiety in perimenopause
• Brain fog and cognitive symptoms
• Joint aching
• Low libido related to oestrogen decline

Long-term protections that HRT provides:

• Bone density — oestrogen is the primary protection against osteoporosis; HRT significantly reduces fracture risk
• Cardiovascular health — when started within 10 years of menopause or before age 60, oestrogen has protective cardiovascular effects
• Possibly cognitive protection — evidence is emerging for reduced dementia risk when HRT is started in the perimenopause window

Types of HRT — and Why the Differences Matter

Oestrogen-only HRT

For women who have had a hysterectomy. Oestrogen alone can be used safely without the addition of progesterone.

Combined HRT (oestrogen + progesterone)

For women with a uterus. Progesterone is added to protect the uterine lining from the proliferative effects of oestrogen alone. The type of progesterone matters significantly.

Bioidentical vs synthetic progestins

This is one of the most important distinctions in HRT. Micronised progesterone (Utrogestan, Prometrium) is structurally identical to the progesterone your body produces and converts to allopregnanolone in the brain — providing calming, sleep-supporting effects. Synthetic progestins (medroxyprogesterone acetate, used in the WHI study) are not equivalent. They do not have the same neurological effects, are associated with higher breast cancer risk, and carry different cardiovascular profiles. The majority of negative HRT headlines have involved synthetic progestins, not micronised progesterone.

Delivery method

• Transdermal (patches, gels, sprays) — oestrogen absorbed through the skin bypasses the liver, does not increase clotting factors, and has a lower risk of blood clots and stroke than oral oestrogen. This is the preferred route for most women.
• Oral tablets — effective but processed by the liver, which slightly increases clotting and cardiovascular risk compared to transdermal
• Vaginal oestrogen — low-dose local oestrogen for urogenital symptoms (dryness, recurrent UTIs, discomfort). Works locally with minimal systemic absorption. Can be used long-term and by women for whom systemic HRT is not appropriate.

What the Evidence Actually Says About Risks

Breast cancer

The most feared risk. The absolute risk increase from combined HRT is small. The WHI study found roughly 8 additional breast cancer cases per 10,000 women per year with combined synthetic HRT — comparable to drinking one glass of wine daily. Micronised progesterone does not appear to carry the same risk increase. Oestrogen-only HRT (for women without a uterus) may actually reduce breast cancer risk. Vaginal oestrogen carries no meaningful systemic risk.

Blood clots and stroke

Oral oestrogen increases clotting factor production in the liver, raising blood clot risk. Transdermal oestrogen does not. For women using transdermal oestrogen (patches, gels), the blood clot risk is not meaningfully elevated above baseline.

Cardiovascular

The timing of HRT start matters enormously. HRT started within 10 years of menopause or before age 60 is associated with cardiovascular benefit — reducing heart disease risk. HRT started more than 10 years after menopause, when arterial disease may already be present, does not have the same benefit and may carry risk in some women.

Who HRT Is Most Appropriate For

• Women with significant vasomotor symptoms (hot flashes, night sweats) affecting quality of life
• Women with sleep disruption, mood instability, or brain fog in perimenopause or early menopause
• Women at risk of osteoporosis
• Women with premature ovarian insufficiency (menopause before 40) — for whom HRT until at least the average age of menopause is strongly recommended for bone and cardiovascular protection
• Women within the "window of opportunity" — within 10 years of menopause or before age 60

Who Should Approach HRT With Caution

• Women with a personal history of oestrogen-receptor-positive breast cancer — requires specialist guidance
• Women with active blood clot conditions or high clotting risk — transdermal oestrogen may still be appropriate
• Women more than 10 years post-menopause starting for the first time
• Women with certain liver conditions

HRT and the Integrative Picture

HRT is a tool — an effective one for many women. It is not the only tool, and for women in early perimenopause with manageable symptoms, lifestyle and systems-based support often produces meaningful results before medication is needed. For women with significant symptoms, HRT and lifestyle support work best together — not as alternatives.

At Srav Health, our practitioners can help you understand your hormonal picture and assess whether HRT, lifestyle medicine, or a combination approach is most appropriate for your situation. Browse our practitioners or take the free snapshot.

Frequently Asked Questions

Is HRT safe?

For most healthy women under 60 or within 10 years of menopause, the benefits of HRT for significant symptoms outweigh the risks. The risk picture varies significantly by type — transdermal oestrogen with micronised progesterone has the most favourable safety profile. HRT should be assessed individually with a practitioner who knows your health history.

Does HRT cause breast cancer?

Combined synthetic HRT carries a small absolute increase in breast cancer risk — comparable to drinking one glass of wine daily. Micronised progesterone does not appear to carry the same risk. Oestrogen-only HRT (for women without a uterus) may reduce breast cancer risk. The risk needs to be weighed against the benefits, including protection against osteoporosis and cardiovascular disease.

What is the difference between bioidentical and synthetic hormones?

Bioidentical hormones are structurally identical to those the body produces. Micronised progesterone is bioidentical and has better safety and tolerability data than synthetic progestins. The majority of negative HRT studies used synthetic progestins — this context matters when interpreting the risk data.

How long can you take HRT?

There is no absolute time limit. Many guidelines previously recommended stopping at 5 years — this is outdated. Current evidence supports continued use as long as benefits outweigh risks, with regular reassessment. For women with premature ovarian insufficiency, HRT until at least the average age of natural menopause (51) is strongly recommended.