Turning the Tables on Hormone Therapy: Why Estrogen Might Be a Hidden Ally for Post‑Surgery Recovery

What’s this about?

Imagine you’re a woman approaching a hip or knee replacement – surgery that most often happens later in life, and often when menopause (and hormone therapy) is on your radar. The conventional wisdom has been: if you’re taking estrogen (known as ERT, estrogen replacement therapy), you may be asked to stop it around surgery because of clotting concerns.

This study asked a different question: what if taking ERT before major joint surgery actually changes the risk of key complications, specifically, venous thromboembolism (VTE, i.e., deep-vein thrombosis or pulmonary embolism) and other “major medical” complications after surgery? This research explores whether continuing estrogen could actually be neutral, or even protective, rather than risky.

When & Who?

The study looked at the years 2015 to 2020, and used a large national database of joint replacement surgeries. In total the data included:

• 893,759 primary total hip arthroplasties (THAs)
  
• 1,660,909 primary total knee arthroplasties (TKAs) (PubMed)
  From these massive pools, the authors pulled out smaller groups of women who had been on ERT within the 90 days before surgery, which was about 3.5 % of each surgery group. For hip replacements: 3,425 women on ERT matched with 6,850 controls. For knee replacements: 7,409 on ERT matched with 14,818 controls. (PubMed) The matching process took into account age, obesity, smoking, diabetes etc., to make the comparison fairer. (PubMed)

So while the ERT cohorts are relatively small, they’re drawn from a huge database, which gives the findings weight.

What did they find?

Here’s where it gets interesting: contrary to what many might expect, the women on ERT did not have higher risk of clotting or complications; in fact, they had lower risk in many cases. Key findings:

• In the hip replacement (THA) group, ERT was associated with roughly half the risk of deep-vein thrombosis (DVT) compared to non-ERT controls (Odds Ratio [OR] ~ 0.52). (PubMed)
  
• In that same hip group, there was no significant difference in pulmonary embolism (PE) risk (OR ~ 0.67, but P=0.31) between ERT vs non-ERT. (PubMed)
  
• Also in the hip group, women on ERT had lower “medical complications” (OR ~ 0.47) following surgery. (PubMed)
  
• In the knee replacement (TKA) group, women on ERT had lower risk across the board: DVT (OR ~ 0.60), PE (OR ~ 0.56), and medical complications (OR ~ 0.53).

In plain language: being on estrogen therapy in the 90 days prior to hip or knee replacement was associated with fewer blood-clot events (especially in knee surgery) and fewer major complications after surgery.

It’s important to note: this is retrospective, association-not causation. The study can’t definitively say “ERT caused the protection”, but the signals are strong.

Why does it matter?

This matters because it challenges a widely held clinical assumption that estrogen therapy must be stopped before major surgery to avoid clot risk. In the world of women’s health, post-menopausal care, bone health and joint replacement this assumption has had real consequences, women discontinuing hormone therapy, perhaps unnecessarily, and possibly losing out on benefits for bone, vascular and joint health.

For women who are on or considering hormone therapy, and who may also face joint replacement (hip or knee), this study opens the door to a more nuanced conversation. It suggests the need for individualised assessment, rather than blanket instructions.

And for those of us navigating mid-life, menopause, joint health and wellness (strength training, mobility, bone support), it brings comfort to know that hormone therapy might not be the “problematic” element around surgery that we once feared.

What am I doing about it?

I already went through two major hip replacements and I wasn’t even asked to stop my HRT, so it’s not an issue. But if it were, then i would bring this study to the table. I’d talk with my surgeon and menopause doctor so that the decision about HRT is part of the broader surgical and wellness plan.

On the wellness side, I would double-down on what I already value: strength training, joint mobility, bone-healthy eating, and ensure my recovery plan is as robust as possible. The hormone therapy piece is one layer in a bigger stack, and this study helps clarify that layer.

Lastly, I am sharing this insight in my network (blog, podcast, friends) because I believe so many of us have been operating under outdated guidance. Empowered with better information, we can ask better questions.

Practical Tips

To put this into real-life action:

• If you’re on HRT and planning a hip/knee replacement: don’t automatically stop your treatment. Bring the study to your surgical team and your hormone provider: ask their take.
  
• Be prepared with timing details: this study focused on ERT use within 90 days of surgery. So know and share when you last took your hormones, when surgery is scheduled, and your full health history (clotting, cardiovascular, bone, etc.).
  
• Discuss clot risk personally: Even though the study shows lower risk, individual factors (history of clotting disorders, family history, other medications) matter.
  
• Coordinate your care team: Your surgeon, your hormone prescribing provider, and your wellness coach/trainer should all be aligned around your overall recovery and ageing plan.
  
• For those not yet facing surgery: View joint health as part of your holistic wellness journey. Hormone therapy + strength/mobility work + bone-health nutrition = a strong foundation for later life.
  
• Share and ask questions: If you’re a wellness professional, blogger or friend supporting others, translate the research into everyday language (“about half the risk”, “fewer complications”) and spark conversation rather than giving one-size advice.
  

This study asks and answers a provocative question: could estrogen therapy, historically stopped around surgery, actually help recovery for hip and knee replacement? What the data show is enough to reconsider old rules and invite smarter, individualised decision-making. As women navigate wellness, aging and possible surgery, that’s an invitation to lean into knowledge, to ask better questions and to shape our care rather than passively follow it.

Disclaimer: This article is for educational purposes only and is not a substitute for personalised medical advice. Always consult your doctor or surgical team before altering hormone therapy or preparing for surgery.

Reference: Zhao, S., Kelly, M., Smith, S., Heckmann, N. D., Schabel, K., Lieberman, E., Yoo, J., & Kagan, R. (2025). Estrogen Replacement Therapy Decreases Associated Risk of Postoperative Venous Thromboemboli and Medical Complications After Total Joint Arthroplasty. The Journal of Arthroplasty, 40(11). (PubMed)