We need to stop talking about testosterone in women as though its only legitimate purpose is sexual desire. And for those few commenters who love to get steamed when I discuss testosterone in women, you can scroll now
Women have androgen receptors throughout the body. We always have. Testosterone participates in muscle maintenance, body composition, physical function, and bone biology. It has never only lived in the “libido” corner.
Today I want to look at one small but fascinating randomized trial that asked a question we still haven’t answered well enough:
Would adding testosterone to estradiol improve women’s bones more than estradiol alone?
To me, that’s a reasonable and important question for women who want to stay strong and independent as we age.
What the study actually did
Researchers enrolled 34 postmenopausal women in a two‑year, randomized, single‑blind trial.
– One group received a 50 mg estradiol implant every three months.
– The other group received the same estradiol implant plus a 50 mg testosterone implant every three months.
Women who still had a uterus also received cyclical progestin. Thirty‑two women completed the study.
So we have two groups:
- Estradiol alone
- Estradiol plus testosterone
What happened to their bones
Both groups gained bone mineral density. That matters. Bone density is critical for independence and healthy aging. Estradiol didn’t just slow bone loss—it increased bone density in the total body, lumbar spine, and hip in both groups. Estradiol is currently FDA‑approved for osteoporosis, and this is one reason why.
But the women who received estradiol plus testosterone gained bone density more rapidly at every site measured.
Compared with estradiol alone, the combined group had significantly greater increases in:
– Total‑body bone mineral density
– Lumbar spine (L1–L4) bone mineral density
– Bone density at the trochanter (upper femur near the hip)
The differences were statistically strong:
– Total body: P < 0.008
– Lumbar vertebrae L1–L4: P < 0.001
– Trochanter: P < 0.005
And there’s more: the estradiol‑plus‑testosterone group was the only group to increase total fat‑free mass—basically lean muscle plus bone.
That combination is not “nice to have.” Muscle and bone work together.
Muscle puts physical load on bone, which tells bone to keep remodeling and stay strong. Muscle also helps balance, stability, and the ability to catch ourselves when we trip. Stronger bones may reduce the damage from a fall. Stronger muscles may reduce the chance of falling at all. That’s real life: can I move confidently, can I live on my own, am I less likely to break a hip at 78.
Testosterone is not just about libido
The study did show greater improvements in sexual function when testosterone was added. Sexual well‑being matters, and we shouldn’t dismiss it.
But sexuality was not the only outcome. The women receiving testosterone had different changes in bone density and lean mass—outcomes directly tied to long‑term independence, mobility, and fracture risk.
This is why I find the nearly exclusive focus on “testosterone = libido booster” so frustrating. It honestly feels a bit sexist. The conversation often stops at “does it increase sex drive?” as though that’s the only part of our lives worth considering.
Meanwhile, we have data hinting at possible benefits for muscle, bone, and overall physical function that barely get discussed.
Where we need to be careful
Now, a reality check.
This was a small trial:
– 34 women enrolled, 32 completed
– It used implants, including a testosterone dose that does not translate directly to the lower‑dose transdermal therapy many women use today
– It measured bone mineral density, not actual fractures over time
– The broader literature on testosterone and bone in women is mixed—some studies show extra skeletal benefit, others don’t
We still do not have large, long‑duration, well‑powered trials to answer a basic clinical question:
> In women already receiving adequate estradiol, does physiological testosterone replacement reduce fractures?
This trial was published in 1995:
Davis SR, McCloud P, Strauss BJG, Burger HG. *Testosterone enhances estradiol’s effects on postmenopausal bone density and sexuality.* Maturitas. 1995;21(3):227–236.
More than 30 years ago, these researchers showed that adding testosterone to estradiol produced significantly greater gains in bone mineral density than estradiol alone in postmenopausal women.
And yet, we still lack enough modern research to answer very basic questions, like:
– Which women might benefit the most?
– Does baseline testosterone or free testosterone matter?
– Does high SHBG change the response?
– What dose and delivery method best match healthy female physiology?
– Does testosterone improve bone quality as well as density?
– Could preserving muscle and bone together reduce falls, frailty, and fractures?
– Does treatment need to begin in perimenopause, before major losses set in?
How estradiol and testosterone might work together
Estradiol and testosterone have overlapping and distinct roles.
– Estradiol is a major regulator of bone remodeling and helps restrain excessive bone breakdown.
– Androgens may act directly through androgen receptors in bone, support lean mass and mechanical loading, and serve as substrate that can be locally converted to estrogen in some tissues.
So when we talk about hormones and bone, it may not be “either/or,” but “how do they work together.”
The bigger issue for women
Here’s what I care about:
We should know whether restoring a more complete female hormonal physiology can preserve not only sexual function, but bone, muscle, mobility, and independence across the many decades we live after menopause.
The fact that we still cannot answer that confidently is not proof that testosterone has no role in women. It’s proof that the question has not been treated as a priority.
And yes, that upsets me.
Not because I think every woman needs testosterone, but because women deserve clear, high‑quality data on tools that may affect whether we stay strong, mobile, and independent into our 70s, 80s, and beyond.
Until we have those answers, I will keep pushing the conversation beyond “libido only” and keep asking for research that reflects the full reality of our bodies and our lives.