You have an operation booked, and somewhere in the pre-assessment paperwork is a question about hormone therapy. The advice you find online contradicts itself, the clinic says one thing and a forum says another, and nobody explains the reasoning. Here is what the question is actually about, and what to ask.
Where we stand: Menova is an independent publication. We sell no hormones, we are not your doctor, and this is general education, not medical advice. Do not stop or continue hormone therapy before surgery based on this article — this is a decision for your surgical team and prescriber together.
What the concern is
Surgery raises the risk of venous thromboembolism — a clot in a deep vein or the lung. That risk comes from immobility, the surgery itself, and the body's response to it.
Oral estrogen also modestly raises clot risk, because it passes through the liver first and affects clotting factor production. The question is whether adding one to the other justifies stopping.
The key distinction, and the one most often missed in general advice:
- Oral estrogen raises clot risk
- Transdermal estrogen — patches, gels, sprays — is not associated with the same increase, because it bypasses first-pass liver metabolism
That single fact changes the answer for most women, and it is the thing to make sure your team knows. See HRT and blood clot risk for the detail.
How the decision is usually made
There is no single universal rule, and practice varies between countries and hospitals. Broadly, teams weigh:
The type of surgery. Major surgery with prolonged immobility — joint replacement, major abdominal or pelvic surgery, anything with a long recovery in bed — carries far more risk than a short day-case procedure. For minor surgery with same-day mobilisation, stopping is often considered unnecessary.
The route of your estrogen. As above. Transdermal is frequently continued where oral would be reconsidered.
Your own risk profile. Previous clot, known clotting disorder, family history, obesity, smoking, cancer, and age all shift the calculation — see family history and menopause.
What thromboprophylaxis you will get. Most surgical patients now receive clot prevention — compression stockings, calf pumps, early mobilisation, and often blood-thinning injections. This is a large part of why blanket stopping has become less common than it once was.
What stopping costs you. Returning hot flashes, broken sleep, and low mood during a recovery period is not trivial. Sleep matters for healing, and this side of the ledger is genuinely part of the decision rather than a complaint to be dismissed.
If you are told to stop
Ask when. Where stopping is advised, it is typically some weeks before surgery — the interval varies, so get a specific date rather than a vague instruction.
Then ask three things:
- "Is this because my estrogen is oral? Would switching to transdermal change the advice?" For some women this is the whole answer.
- "What can I use for symptoms while I'm off it?" Non-hormonal options exist and a recovery period is a bad time to be unmedicated — see non-hormonal prescription options and the full non-hormonal toolkit.
- "When do I restart, and what needs to be true first?" Usually once you are properly mobile. Get it written down, because this is the step most often forgotten after discharge.
Things that are usually not affected
Vaginal estrogen. Local low-dose vaginal estrogen produces minimal systemic absorption and is generally not treated the same way as systemic therapy. Confirm with your team, but do not assume it must stop — see is vaginal estrogen safe.
Progestogen alone, including a hormonal IUD, is a different question from estrogen and is usually handled differently.
Testosterone, where prescribed, is again separate — see testosterone for women.
Say precisely what you take. "I'm on HRT" is not enough information for a good answer.
What to tell the pre-assessment team
Bring the specifics, because the person doing your pre-assessment may not be a menopause specialist:
- The exact product, dose, and route — "50 microgram estradiol patch twice weekly" rather than "a patch"
- Your progestogen, separately, including an IUD
- Any vaginal estrogen, which women routinely forget to mention
- Any personal or family history of clots
- Anything else that affects clotting, including recent long-haul travel
After the operation
- Move as early as you are allowed to. Early mobilisation is one of the most effective clot-prevention measures there is
- Use the stockings and pumps properly, dull as they are
- Know the warning signs and act on them: pain, swelling, warmth or redness in one calf; sudden breathlessness; chest pain worse on breathing in; coughing blood. Seek emergency care for these — during recovery and for several weeks afterwards
- Restart on the agreed schedule, and chase it if nobody raises it
If surgery will cause menopause
A different situation entirely. If your operation involves removing both ovaries, menopause begins immediately and abruptly rather than gradually, and the hormone conversation should happen before surgery rather than afterwards — particularly if you are under the usual age of menopause. See early and surgical menopause and hysterectomy and menopause.
The one thing to take away
Do not stop hormone therapy on your own initiative because you read that you should, and do not quietly continue it without telling anyone. Both are worse than asking. The answer depends on your route, your surgery, and your risk profile, and it is a five-minute conversation that most teams are happy to have.
Our free printable visit prep sheet gives you a page to list your exact products and questions for pre-assessment. The free 2-minute self-check covers your wider symptom picture — no account, not a diagnosis, and your answers never leave your device.
This article is general education, not medical advice. Decisions about hormone therapy around surgery must be made with your surgical team and prescriber. Seek emergency care for symptoms of a blood clot or pulmonary embolism.
Sources: NICE NG89 — Venous Thromboembolism in Over 16s, The Menopause Society, NHS — HRT, and ACOG.