By Dr. John A. Robinson, NMD & Dr. Cristina Romero-Bosch, NMD
The Hormone Zone
For decades, testosterone in women has been discussed primarily through the lens of libido, muscle, energy and sexual health. When fertility enters the conversation, estrogen, progesterone, FSH, LH and AMH tend to dominate. But testosterone deserves a place in that conversation as well. Androgens are normal ovarian hormones, androgen receptors exist within developing follicles, and appropriate androgen signaling appears to participate directly in follicular development.
This raises an intriguing question: Could inadequate testosterone contribute to poor ovarian function in some women, and could restoring appropriate androgen signaling improve fertility? Possibly, but there is an important qualification. Most of the clinical evidence comes from women undergoing IVF who have demonstrated poor ovarian response. We do not yet have comparable evidence demonstrating that testosterone improves natural conception.
Testosterone Is an Ovarian Hormone
Calling testosterone a “male hormone” has probably done women a disservice. Women naturally produce testosterone from the ovaries and adrenal glands, and ovarian follicles contain androgen receptors. Research suggests androgen signaling is particularly important during pre-antral and antral follicular development. Testosterone may influence granulosa cells and FSH signaling, potentially helping developing follicles become more responsive to FSH.
The goal, however, isn’t high testosterone; it is appropriate androgen signaling. Too much androgen can interfere with ovarian physiology, as we see in hyperandrogenic PCOS, but inadequate androgen signaling may also be problematic. Normal ovarian physiology appears to depend upon balance.
The Study That Got Our Attention
In 2006, Balasch and colleagues published an intriguing study in Human Reproduction involving 25 women who had experienced two previous IVF cycles cancelled because of poor follicular response, despite aggressive gonadotropin stimulation. Before another stimulation cycle, researchers administered transdermal testosterone at 20 micrograms/kg/day for five days immediately before ovarian stimulation. For a 60-kg woman, that corresponds to approximately 1.2 mg of delivered testosterone per day.
The results were striking: 20 of 25 women—80%—demonstrated substantially improved follicular recruitment. Among responders, approximately 5.8 oocytes were retrieved on average, and investigators reported a clinical pregnancy rate of 30% per retrieval. This was a small, nonrandomized study, so it isn’t definitive proof, but it raised an important possibility: perhaps some ovaries respond poorly not simply because they need more FSH, but because the follicles aren’t adequately prepared to respond to FSH.
What Has Happened Since?
Subsequent randomized trials investigated testosterone pretreatment in women classified as poor ovarian responders. A 2022 systematic review examined eight randomized trials involving 797 women. Testosterone gel doses were generally around 10–12.5 mg applied daily, with treatment periods ranging from 10 to 56 days. Across these studies, testosterone pretreatment was associated with higher live-birth and clinical-pregnancy rates, more retrieved oocytes, lower gonadotropin requirements and fewer cycle cancellations.
A 2019 meta-analysis similarly reported higher live-birth and clinical-pregnancy rates and modest increases in mature oocytes and embryos. More recently, a 2024 Cochrane review evaluated eight randomized trials involving 716 women for live birth or ongoing pregnancy. Testosterone pretreatment was associated with an odds ratio of 2.53 for live birth or ongoing pregnancy compared with placebo or no treatment. These findings certainly deserve attention, but they do not settle the question.
Why Isn’t Testosterone Standard Fertility Treatment?
Despite these encouraging findings, testosterone pretreatment isn’t routinely recommended for women undergoing IVF. The studies remain relatively small, protocols vary considerably, and we still don’t know the optimal dose, duration or patient population. Safety reporting has also been limited. The 2025 ESHRE ovarian-stimulation guideline therefore does not recommend testosterone pretreatment routinely for predicted low responders.
What we have, then, is a meaningful biological signal supported by encouraging clinical evidence, but not yet a standardized fertility protocol. This is an important distinction because promising evidence should stimulate additional research rather than encourage indiscriminate testosterone use.
What About Natural Fertility?
This is where extrapolation becomes particularly important. These studies primarily involved poor ovarian responders undergoing controlled ovarian stimulation for IVF, and the women subsequently received potent gonadotropin stimulation. We therefore cannot take these studies and conclude that testosterone increases natural fertility; that has not been demonstrated.
But there is a more interesting question. If androgens are physiologically involved in follicular development, what happens when a reproductive-age woman has genuinely inadequate androgen availability? That question becomes particularly relevant in women with diminished ovarian reserve, unexpectedly poor follicular development, previous poor ovarian response or very low circulating testosterone.
Rather than viewing testosterone exclusively through sexual function, reproductive medicine should continue investigating whether physiologic androgen deficiency represents an overlooked component of ovarian health in selected women. That is very different from suggesting that every woman trying to become pregnant should take testosterone.
More Testosterone Is Not the Answer
If inadequate androgen signaling can impair follicular development, it does not follow that increasingly higher testosterone produces better fertility. Excessive androgen exposure can interfere with ovulation and normal follicular development. The real clinical question therefore isn’t, “Should women trying to become pregnant take testosterone?” It is whether we are adequately evaluating androgen physiology when assessing female reproductive health.
This distinction matters because hormone optimization should be about restoring physiology, not simply driving hormone concentrations upward. Fertility depends on an extraordinarily coordinated endocrine environment involving estrogen, progesterone, testosterone, FSH, LH, thyroid hormones, insulin signaling and numerous local ovarian factors.
A Bigger Lesson About Women’s Hormones
We have worked with women’s hormones for decades, and one recurring problem is medicine’s tendency to divide hormones into simplistic categories: estrogen is the “female hormone,” while testosterone is the “male hormone.” Human physiology is far more sophisticated. Women need estrogen and progesterone, but women also need testosterone, and the emerging fertility literature gives us another reason to stop treating testosterone as an optional hormone that matters only when a woman complains about libido.
For women struggling with fertility, diminished ovarian reserve or poor ovarian responsiveness, testosterone is not yet a proven stand-alone fertility treatment. But androgen physiology may represent another important piece of the reproductive puzzle. At The Hormone Zone, the larger lesson is to avoid evaluating one hormone or laboratory number in isolation and instead understand the entire hormonal environment in which the body is trying to function. Sometimes the hormone everyone assumed belonged primarily to men may turn out to be remarkably important to women.
Selected References
Balasch J, Fábregues F, Peñarrubia J, et al. Pretreatment with transdermal testosterone may improve ovarian response to gonadotrophins in poor-responder IVF patients with normal basal concentrations of FSH. Human Reproduction. 2006;21(7):1884–1893.
Noventa M, Vitagliano A, Andrisani A, et al. Testosterone therapy for women with poor ovarian response undergoing IVF: a meta-analysis of randomized controlled trials. Journal of Assisted Reproduction and Genetics. 2019;36:673–683.
Naik S, Lepine S, Nagels HE, et al. Androgens (dehydroepiandrosterone or testosterone) for women undergoing assisted reproduction. Cochrane Database of Systematic Reviews. 2024.
European Society of Human Reproduction and Embryology. ESHRE Guideline: Ovarian Stimulation for IVF/ICSI. Updated 2025.
