For postmenopausal women, a boost of testosterone can light up libido ‒ just don’t believe all the online hype on its benefits.
In Greek mythology, the goddess Aphrodite was born from the discarded testicles of Uranos, thrown into the sea. It’s an example of the power of the testes being celebrated, even before humans understood the source of that power.
The hormone testosterone wasn’t discovered until 1935, by scientists in Holland, Germany and Switzerland, in the early days of endocrinology. Long before this, though, its effects were known. In antiquity, and up until the early 20th century in some cultures, men were castrated to produce obedient, infertile servants and slaves (the fate of some of the millions of men kidnapped from Africa), as punishment, or to preserve prepubescent soprano voices. The last Chinese eunuch, Sun Yaoting, died, aged 94, in 1996.
In the 19th century, physicians experimented with organotherapy – extracts of dog and guinea pig testes administered to humans for apparent rejuvenating effects. It’s thought those effects were only ever a placebo, but the instinct, that here was an “invigorating” substance, did pave the way for modern and more effective hormone treatments.
It wasn’t until much later that scientists realised that women, too, produce testosterone, and need it for certain bodily functions (just as men also produce forms of oestrogen). It’s produced in the ovaries, in the adrenal gland, and in peripheral tissues such as bone, muscle and fat. Testosterone is used in those tissues, and it’s also converted into other hormones, including oestradiol, a form of oestrogen. It plays a role in bone and muscle health, fertility and libido, among many other functions.
Unlike oestrogen, though, women’s testosterone levels don’t dive off a cliff at menopause. Instead, they slowly decline from their 20s until their 70s, when some studies suggest there might be a bit of a rise, for reasons as yet unknown.
In the late 1950s, the earliest reports of an association between women with low sex drive and low testosterone levels appeared. But treating women with testosterone is a practice that’s dragged far behind the hormone’s use in men, and it’s had its fair share of false starts. A testosterone patch – much like the oestrogen patches used in modern hormone replacement therapy (HRT) – was developed and tested by Proctor & Gamble in the early 2000s. It was shelved because it faced rejection from the US Food and Drug Administration at a time when hormone treatment for women was thought to be risky.
Fast forward 20 years and the landscape has changed. New generations of women are hitting midlife, perimenopause and menopause, and the Millennials and Gen Xers don’t want to retire – from sex or from life – as their mothers might have. Enter a new breed of medical influencers who claim that testosterone is the missing piece of the treatment puzzle for menopausal women.
Enter a new breed of medical influencers who claim testosterone is the missing piece of the treatment puzzle.
Miracle drug?
Prominent UK GP Dr Louise Newson, who runs a string of menopause clinics and has done much to raise awareness of menopause in the UK, is a testosterone fan. In an Instagram video on the subject, she describes an array of symptoms for what she calls a “testosterone deficiency”.
“A lot of women who are testosterone deficient say they just feel joyless; they feel emotionless, they feel quite numb … their zest for life has gone,” she says. She lists low mood, anxiety, poor sleep, palpitations, flushes, lightheadedness, rumination and the inability to think clearly as potential symptoms, along with dry eyes, muscle and joint pain, skin and hair problems and bladder and pelvic floor issues.
Professor Susan Davis of Melbourne’s Monash University has been immersed in the study of hormones in women for decades. She conducted the first randomised trial of testosterone in women in the early 1990s. She told the Listener that after excitement at her early work – which showed intriguing potential benefits from testosterone – the medical and research communities backed away from studying hormones in the wake of the controversial 2002 Women’s Health Initiative study into HRT. Results inaccurately showed HRT caused breast cancer, stroke and blood clots.
Now, the situation has changed again. The cancer risk of HRT is considered to be much smaller than the 2002 study reported.
But while many women are benefiting from hormone therapy, the attention on testosterone is still controversial.
“In the clinical academic world there have been very divided camps of people,” says Davis. “You’ve got the real [testosterone] naysayers who just don’t believe there’s any benefit and then you’ve got this whole underground of doctors who are just evangelists about testosterone and prescribe high doses.”
The evangelists, like Newson, claim a host of benefits, from improved memory, better cognition and mood to preserving bone and muscle mass and protecting the heart, as well as restoring general wellbeing.
They’re not shy about spreading the message in social and mainstream media. The tone of this content creates the impression, say some, that women are missing out if they’re not adding testosterone to their HRT regimes.
US-based gynaecologist Jen Gunter is an outspoken critic of this messaging. She noted recently in her newsletter, The Vajenda: “If you only got your information from social media, you couldn’t be faulted for thinking that testosterone cures everything, is the veritable fountain of youth, and is also an admission ticket to a super-secret cool girls club.”
But Newson says she’s convinced the symptoms she describes are related to low testosterone because she first eliminates other medical causes in her patients. Most importantly, she says, when she gives women testosterone therapy, “the joy comes back”.
If you got your information only from social media, you couldn’t be faulted for thinking testosterone cures everything.
Libido benefits
The conflicting messages are confusing for women because the positive claims seem not without foundation. Davis’s early trial found women who got testosterone treatment (in addition to oestrogen) had improvements in sexual function, bone density and lean mass, with no adverse effects on cholesterol levels.
Now, though, as a body of evidence has accumulated, Davis says she is “in the middle camp” on testosterone. She’s convinced of its benefits for low libido and is not worried about harm. There is, she says, “irrefutable evidence” that when postmenopausal women with troublesome low libido are treated with testosterone, they get a benefit, including more of what the research terms “satisfactory sexual events”.
“The gold standard research shows that if we look at desire, [testosterone] improves arousal; it increases orgasm frequency and sexual distress is reduced,” says Davis.
At the same time, she’s forthright about some of the content online about testosterone and general wellbeing. “They’re bullshit,” she says of lists that are found – on apparently credible websites – of “signs of low testosterone” in women.
“We haven’t been able to find [those symptoms],” she says, pointing to numerous trials and meta analyses conducted by her team and other researchers. This evidence has shown a wide range of testosterone levels in women of all ages and stages; levels that can’t always be pinned to particular symptoms.
You’ve got to look at the totality of the literature, and if people aren’t doing that, then they’re making big mistakes.
“There’s no evidence that women with low testosterone are any different to women with high testosterone,” Davis stresses. “I see some patients with high testosterone, and they’ve got no symptoms. And we have women who are hirsute, with acne [signs of high testosterone] who have normal testosterone levels.”
Testosterone cheerleaders are taking positive findings showing benefit, being selective with the data and running with it, she says. “Not only are they cherry-picking data, but even [with] the data they cherry-pick, they’re over-interpreting it to claim a benefit.”
She’s supported in that view by all the global menopause bodies, including the International Menopause Society and similar societies of North America and Australasia. Guidelines from these organisations all say testosterone is suitable only as a treatment for low libido in postmenopausal women – and even then, it works only some of the time.
The jury is still out on any other benefits, though research continues, including in Davis’s team, where testosterone is the subject of ongoing trials in women. She presented at the recent International Menopause Society’s congress on the evidence to date, where she concluded, “Testosterone is complex. It’s fascinating … and a lot of clinical trials are still needed.”
Davis wants people to pay attention to the body of evidence, not just individual pieces of research. “There are very few times in medicine where we make quantum leaps of knowledge,” she says. “You’ve got to look at the totality of the literature, and if people aren’t doing that, then they’re making big mistakes.”
But I feel better …
It’s clear that whatever the global experts say, women around the world, including in New Zealand, are being prescribed testosterone – and sometimes off label, with a nudge and a wink about what it’s actually for.
In Hawke’s Bay, Sarah (not her real name) has been using testosterone treatment for a year. At 54, she’s postmenopausal and had been taking oestrogen and progesterone HRT for a few years. Still, she says, she wasn’t feeling great. “I had really low mood and no motivation. I’d put on loads and loads of weight. And I had really horrendous joint pain. I’d wake up in the morning and I’d have to crawl to the toilet.”
She says her doctor told her a lot of research was saying testosterone helped with things like joint pain, mood and motivation and suggested she try it.
There were a couple of provisos: the medication wasn’t funded, so Sarah would have to pay. “She [also] said: ‘You need to tell me you’re having issues in the bedroom, and you have no libido, in order for me to prescribe this.” Other women report similar coaching from their GPs, or at least no real objections when they ask to try it.
“I told my doctor I wasn’t feeling quite right and wanted to try [testosterone],” says Claire, a 49-year-old Aucklander. “I had blood tests, and that was it. For me, it was the last piece of the puzzle.”
The medication these women are using is AndroFeme, a transdermal testosterone cream. It’s the only product of its kind globally. Designed specifically for women, it’s produced by Western Australia’s Lawley Pharmaceuticals.
Lawley began in a small pharmacy in Perth in 1990, where pharmacist Michael Buckley began compounding products his patients couldn’t find elsewhere. It’s grown – largely off the back of testosterone – into a global enterprise. The first version of AndroFeme was created in 1999, and Buckley says the company has been “chugging away quietly in the background” while hormone therapy has been through ups and downs in popularity.
AndroFeme is carefully promoted to physicians for just its licensed use – hypoactive sexual desire disorder (HSDD), another name for low libido in women. At the menopause congress, the AndroFeme stand swarmed with doctors from around the world keen to know how they could access the product. There were three separate presentations on testosterone at the conference; all in packed rooms.
In most countries, apart from Australia, South Africa and New Zealand, women who are prescribed testosterone must use a product intended for men and adjust the dose significantly in order to avoid side effects. A male testosterone gel, Testogel, intended for use in men and people in gender-affirming therapy, was approved by Medsafe here last April and is fully funded. About 1700 women were dispensed Testogel within the first eight months of it gaining approval, Pharmac figures show.
In New Zealand, AndroFeme has not been approved but is currently accessible under section 29 of the Medicines Act. Any doctor can prescribe it but many don’t know about it. It’s imported by some pharmacies and costs about $150 for a supply of two to three months.
Buckley estimates there are about 1500 users in New Zealand, but he suspects the number of women on male testosterone medication will climb. In the UK, where Testogel is NHS funded but women must pay £100 for AndroFeme, research indicates for every woman on AndroFeme, there are about 20 male testosterone users.
What don’t we know?
Assuming women are using appropriate doses, if they feel better on testosterone, is there harm? There can be, though side effects are more common for women using male products, where it’s easy to accidentally overdose. More testosterone is not always better. Symptoms can be permanent ‒ including voice changes and enlargement of the clitoris ‒ and reversible, including acne and hair loss. Endocrinologists here have voiced concerns about GPs prescribing Testogel to menopausal women, largely because of the danger of doses being too high.
Napier GP Samantha Newman, who specialises in women’s health, says she’s careful to explain all of this to her patients, along with the point that there’s not a lot of long-term data on testosterone use in women. She prescribes it according to its licensed use, for libido, but does find some of her patients experience other benefits, too, such as improvements in cognition, brain fog and motivation.
“When I’m prescribing testosterone, I never do it in one consult,” she says. “I always give people information to read. I go over it with them and I describe exactly the steps of administering the medication. And I have baseline blood tests done, and ongoing tests to ensure it doesn’t go high.”
Newman says starting on testosterone is about shared decision-making, and she makes sure her patients know it can take months to notice any improvement. “Whenever I start anyone on it, I’m like, ‘You may notice it straight away, but you may not. It may be three, six [or] nine months. So, does that [duration] align with your health journey and your ability to administer a medicine daily?’”
Another point experts stress is that we don’t know what we don’t know. Davis points out there are no normal ranges for testosterone and despite what the internet says, we don’t really know what “normal” levels of testosterone are for women.
Blood testing for testosterone is also fraught. The levels of testosterone in women’s bodies are far lower than those of men, and the tests available to measure them were designed for men. Tests are notoriously inaccurate. On top of that, the way testosterone is converted and used in the body means measuring it in the blood isn’t necessarily an indicator of how well it’s performing its various functions. As a result, testing in women is recommended only as a safety check, to make sure they’re not absorbing too much when they’re using it as a therapy.
Mood wise, I don’t feel anxious, I don’t feel depressed. I don’t want to stab my husband in the eye with a fork.
Clear path forward
Buckley is excited about the future for testosterone in women. He’s hoping – off the back of research now under way – to be able to license AndroFeme for conditions other than HSDD. He believes testosterone will likely be considered part of standard HRT further down the track.
“Where I think these studies will take us is that it will bring testosterone out of the cold and bring it in as part of a triple-therapy hormone replacement therapy.”
“It could be five or 10 years … [but] I have little doubt,” he says. “And neither do all the key opinion leaders in the world. But the work has to be done.”
He’s awaiting approval for AndroFeme by both NZ’s Medsafe and – more lucratively – UK regulatory agency. In the meantime, he says, “When you have physicians who are treating patients and seeing them improve dramatically using a triple therapy, they’re going to prescribe it for people.”
Susan Davis is excited about her ongoing testosterone work, too, though like a good scientist, she says she is “agnostic” about the outcomes. Her team is working on large, randomised control trials looking at testosterone levels in women and how they relate to muscle function, muscle mass and performance as well as bone health and heart failure. The researchers are using sophisticated measuring tools, she says, so “our findings should be very meaningful”.
Davis wants women to know that testosterone is a vital female hormone, one scientists are still trying to understand. “Watch this space,” she says. Right now, though, “I certainly don’t advocate that it’s a missing hormone everyone should have at menopause.”
A year in, Sarah doesn’t need evidence – she’s a testosterone convert. “I’ve gone from barely being able to move, to being able to get out there with no problems. My pain’s more or less disappeared. I’m now exercising anything from three to six times a week.”
And there’s more. “I think of it as getting my mojo back, really. I’m just a lot more motivated. I volunteer two days a week now. And I want to be here. I’m not sitting in bed in the morning despairing and thinking, ‘Oh, what’s the point?’”
She feels ready to go back to work full time. “Just mood wise, I don’t feel anxious. I don’t feel depressed. I don’t want to stab my husband in the eye with a fork.”
She can’t see a reason to ever stop testosterone. “Honestly, they’ll need to prise it out of my cold, dead hands.”
You’re the man
Positions of power and levels of testosterone seem to go hand in hand
It’s possible hormone levels are not born, but made, according to some research. A study published in the US journal Proceedings of the National Academy of Sciences in 2015 looked at gender socialisation and how it affects sex hormones – specifically testosterone. Researchers came up with a unique experiment: participants – all trained actors – acted out monologues where they were required to wield power in different ways. Their characters played bosses firing an employee. In one scenario, they used traditionally “masculine” behaviours – taking up space, dominant body language, not smiling – and in another, they used “feminine” traits, including frequent smiles, hesitancy and a higher tone of voice. Their testosterone levels were measured before and after.
For the women in the study, it was found that wielding power increased testosterone, regardless of whether it was performed in a gender-stereotyped masculine or feminine way. In other words, even acting like they have power boosts testosterone in women.
For the men, the testosterone boost was there, but much less pronounced. The researchers suggest men are socialised to wield power and to compete, and these gender stereotypes affect testosterone levels. “A lifetime of gender socialisation could contribute to sex differences in testosterone,” they concluded. The experiment raised further questions about “gender to testosterone pathways” including the effects of socialisation on human biology.
The findings were echoed by other research: testosterone falls when men become fathers. Single men with higher testosterone are more likely to find partners – there’s that competition again. Once they’re in a stable partnership and become fathers, though, these men have a sharp decline in testosterone. And men who are most involved in childcare have lower testosterone than those who don’t.
Another recent study, on gerbils, found testosterone – which is known to promote aggression in males – also had the surprising effect of promoting socialised behaviour in the right context. Expectant-father gerbils got more “cuddly” when given extra testosterone, not less. The suggestion is that testosterone enhances “context-appropriate” behaviour, whether that’s nurturing or aggression.