Bioidentical hormone replacement therapy (BHRT) carries risks broadly similar to those of conventional HRT, including an increased chance of breast cancer, blood clots, stroke, and endometrial cancer.
Compounded BHRT preparations introduce additional considerations around quality standards and the importance of adequate progestogen inclusion. Common side effects include weight changes, acne, mood swings, bloating, and breast tenderness.
Individual risk varies significantly depending on age, personal health history, family history, how long therapy is used, and the delivery form chosen.
Understanding these risks is an important part of any conversation with a healthcare provider before starting treatment.
The information in this post is for educational purposes only and does not constitute medical advice. Please consult a qualified healthcare professional before making any decisions about hormone therapy.
Key Risks of Bioidentical Hormone Replacement Therapy
The risks associated with BHRT overlap significantly with those of conventional HRT.
Here is what the current evidence shows across the main risk categories.
Breast Cancer
Long-term use of combined BHRT (oestrogen plus progesterone) for five or more years is associated with a slightly increased risk of breast cancer.
The risk appears primarily linked to combined therapy rather than oestrogen alone. Women who have had a hysterectomy and use oestrogen-only therapy may face a lower breast cancer risk, though individual circumstances vary.
Personal and family history of breast cancer is an important factor when assessing individual risk.
Studies suggest that risk returns toward baseline after stopping therapy, though how quickly this occurs differs between women.
Endometrial and Uterine Cancer
Oestrogen taken without progestogen can cause the uterine lining to thicken over time, increasing the risk of endometrial and uterine cancer.
This is why a progestogen (either progesterone or a synthetic progestogen) is prescribed alongside oestrogen for women who have not had a hysterectomy. It is a protective measure, not an optional addition.
In compounded BHRT, ensuring the progestogen component is correctly included and adequately dosed is particularly important.
Women using compounded preparations should confirm with their prescribing doctor that endometrial protection is built into their formulation.
Cardiovascular Risks: Blood Clots and Stroke
Oral oestrogen is associated with a small increased risk of venous thromboembolism, which refers to blood clots forming in the veins.
The risk of stroke is also slightly elevated with oral HRT, particularly in women who begin therapy more than ten years after menopause. Transdermal delivery forms such as creams, gels, and skin patches are generally associated with a lower risk of blood clots than oral tablets, and are often preferred for women where cardiovascular risk is a consideration.
Cardiovascular risk is higher in older women and those with pre-existing heart disease or a personal history of blood clots.
Common Side Effects
Many women experience side effects in the early weeks of starting BHRT as the body adjusts to changing hormone levels.
Common side effects include bloating, weight gain, breast tenderness, acne, irregular bleeding, and mood swings. Most are dose-related and tend to improve once the dose or delivery form is adjusted by a prescribing doctor.
Hot flushes and night sweats sometimes worsen temporarily before improving as hormone levels stabilise.
If side effects persist beyond the initial adjustment period, it is worth discussing formulation changes with both the prescribing doctor and compounding pharmacist.
Who Faces Higher or Lower Risk?
Risk is not the same for every woman, and individual risk profiles vary considerably.
Women who face a higher risk profile include those aged over 60, those who begin HRT more than ten years after menopause, and those with a personal or family history of breast cancer, blood clots, stroke, uterine cancer, or liver disease.
A lower risk profile is generally associated with women who start therapy closer to the onset of menopause, use the lowest effective dose, use therapy for the shortest appropriate duration, and choose transdermal rather than oral oestrogen delivery.
Risk also changes over time. A risk calculation that makes sense at 50 may look different at 65, which is why regular review with a healthcare provider is important rather than remaining on the same formulation indefinitely.
Balancing Risks Against Benefits
For many women, BHRT provides meaningful relief from symptoms that significantly affect daily life: hot flushes, night sweats, vaginal dryness, mood changes, and disrupted sleep.
The question is not simply whether risk exists, but whether the benefits of symptom relief and quality-of-life improvement outweigh an individual’s specific risk profile.
For some women, particularly those with severe menopausal symptoms at a younger age, the balance may clearly favour treatment. For others, a more cautious approach may be appropriate.
The goal of any hormone therapy is always the lowest effective dose for the shortest duration that achieves symptom control, reviewed regularly as circumstances change.
Learn More about BHRT at McKenzie’s Compounding Chemist Today!
Understanding the risks of BHRT is the starting point for an informed conversation with a healthcare provider, not a reason to avoid the conversation altogether.
At McKenzies Compounding Chemist, our experienced compounding pharmacists work alongside prescribing doctors to prepare individualised BHRT formulations using pharmaceutical-grade ingredients. Every formulation is tailored to the prescribing doctor’s specifications and prepared to high compounding standards.
Get in touch with our team to learn more about our compounded BHRT services, or submit your prescription online to get started.