A study just published in the Journal of Sexual Medicine in August 2026 out of Baylor College of Medicine and Newson Research is one I want every woman on hormone therapy to read. Because it directly addresses one of the most common and most frustrating clinical scenarios I see: the woman who is already on estrogen and progesterone, doing everything right, and still not feeling well.
The Study:
The study was done on 279 women, already on transdermal hormone replacement therapy, estrogen with or without progesterone, for a minimum of three months. Researchers added transdermal testosterone to their existing regimen and measured 24 symptoms across eight body systems before and after, using a validated questionnaire, and the follow-up was at three months.
Symptoms Experienced Before Testosterone Was Added (but on standard MHT)
- 92.9% had significant fatigue
- 89.6% had decreased libido
- 88.9% had memory impairment
- 86.4% had concentration difficulties
- 82.1% had irritability
The single most bothersome symptom was low libido rated quite a bit or extremely bothersome by 63.4% of participants. Fatigue ranked second at 47.7%. Memory problems third at 38%. Musculoskeletal pain fourth at 33%. So, for them, estrogen and progesterone alone were not enough. Something was still missing.
After Three Months of Adding Testosterone
15 out of 24 symptoms improved significantly -
- Vaginal dryness - improved 59%
- Hot flashes- improved 54.9%
- Libido - improved 54.8%
Energy, mood, cognitive function, musculoskeletal symptoms, and genitourinary symptoms all showed statistically significant improvement across the board. And, not a single symptom got worse.
The only categories that did not show significant change were neuropathic and cardiopulmonary symptoms, everything else moved meaningfully in a positive direction within just three months.
The Vaginal Dryness and Hot Flash Numbers Are Important to Remember
Most people, including most providers, do not associate testosterone with vaginal health or hot flashes. Estrogen is the primary driver of both. But this study shows that testosterone has a meaningful and independent role.
Vaginal and vulvar tissue contains androgen receptors. Testosterone contributes to tissue integrity, sensation, and moisture independently of estrogen. And while the exact mechanism behind the hot flash improvement needs further investigation, the clinical signal here is real, statistically significant, and consistent across nearly 280 women.
The Bigger Picture
Testosterone is the most abundant sex hormone in women across their reproductive years. It declines significantly through the 30s and 40s, and that decline accelerates in perimenopause and menopause. Testosterone receptors are found in the brain, muscle, bone, vaginal tissue, bladder, skin, and joints. Which is why its deficiency produces symptoms across so many systems simultaneously, and why treating it produces improvements across so many systems at once.
Currently there is no FDA-approved testosterone formulation for women in the United States. It is prescribed off-label. And as a result, it is often never offered at all or it is offered, but in the wrong doses. Current guidelines recommend it only for low libido in menopausal women. But this study makes a compelling case that the clinical benefits extend far beyond sexual desire alone.
What the Authors Concluded:
The study's own conclusion: the addition of testosterone therapy to standard HRT may create a synergistic effect, further improving menopausal symptoms across various organ systems. In other words, testosterone and estrogen together do more than either one does alone.
However, it does have some limitations. It was retrospective with no control group. Some women had HRT adjustments made at the same time as testosterone was added, which may have influenced outcomes. Follow-up was three months, meaningful but not long-term. And women seeking specialist care may have more severe symptoms than the general population. So, prospective, controlled trials are definitely needed.
What This Means at The Lee Clinic
Testosterone is not an afterthought in how we approach hormone care. It is a routine part of every patient evaluation: checked, discussed, and addressed when indicated, as part of a complete hormonal picture alongside estrogen and progesterone.
If you are on hormone therapy and still struggling with fatigue, brain fog, low libido, joint pain, or mood changes and nobody has talked to you about testosterone, that conversation is overdue and it is one we are ready to have with you.
Hernandez BS, Boyne AM, Fleming B, Saffati G, Benton JZ, Hinojosa-Gonzalez DE, Dunnam S, Gudlavalleti H, Kamal A, Neville A, Lichtveld G, Khera M, Newson L. Improvement in multiple organ systems following testosterone replacement therapy in women previously on standard hormone replacement therapy. The Journal of Sexual Medicine. 2026;23(9):qdag116.
The Lee Clinic sees patients in person in Winchester and Reston, VA. Telehealth appointments are available for patients in FL, DC, WV, and MD. Call us at 540-542-1700 to schedule.