Bronwyn Graham: Pop quiz. Hands up, who knows what this is? This, this.

Laughter

Come on, you gotta know, hands up. Now, hands up, who knows what this is?

Audience responds

Oh, very good audience. As far back as the year 1500, Leonardo da Vinci was drawing startlingly accurate anatomical sketches of the male penis.

Fast forward nearly 500 years to 1997. We've flown to the moon. Wi-Fi, just been invented.

Spice Girls, taken the world by storm. But the clitoris still isn't in your doctor's copy of Grey's Anatomy. It wasn't until 1998 that Australian neurologist Professor Helen O'Connell fully mapped the clitoris, which, by the way, she did in her spare time, unfunded.

She's currently searching for the G-spot and on that journey, we wish her well.

Laughter

And I just think we need to take a moment of appreciation for Helen, the unsung hero.

Audience applause

And maybe start up a GoFundHelen campaign.

Or at the very least, put her face on a coin, one of the small ones.

Laughter

So how does this happen? How was it that an entire body part was missing from anatomy books right up until the end of the 20th century? Well, the answer's quite simple. It is rather difficult to find the clitoris on a male body.

You see, for centuries, scientists have viewed the male body as the status quo, as the truest representation of what it is to be human. And this means that in our quest to understand how the human body works in health and in disease, scientists have had an overwhelming preference to study males rather than females. Even today, the vast majority of biomedical research in rats and mice, which is where scientists work out why diseases occur and how to treat them, is only done in males.

It wasn't until 1993 that the USA mandated that women must be included in human clinical trials, where drugs are tested for safety and effectiveness. But there are still more men than women in clinical trials today. And many countries still don't have mandated inclusion of females in biomedical research.

Not very important countries, mind you, just places like the UK and our very own Australia. I mean, come on. The USA, who is casually stripping women of their reproductive freedoms like they're in some Margaret Atwood novel, has mandated inclusion of females in medical research, and we don't? Australia, this is mightily embarrassing.

But it's beyond embarrassing, because this talk isn't just a tale of the missing clitoris. It's bigger than that. What I'm telling you is that medicine in women isn't evidence-based.

Women, your healthcare is based on a man's body. The fallout? Women, you are 50% more likely to experience adverse reactions to drugs and vaccines than a man. Pain medications and anesthetics don't work as effectively in you as they do in men, so you're more likely to develop chronic pain conditions and addictions to pain medications.

And there are hordes of seriously understudied medical conditions that only impact females because it's very difficult to investigate endometriosis, ovarian cancer, and how to prevent or manage a prolapsed uterus after childbirth in males who don't possess ovaries or a uterus. So, how did we end up in this absolute bin fire of a situation? The answer is a rather depressing reiteration of a theme across human history. Scientists are afraid of the menstrual cycle.

Is it the blood? The absolute sorcery of being able to bleed for seven days and live to tell the tale?

Laughter

In part, perhaps. But mostly, it's the sex hormones. Scientists are afraid that if we include females in research with their messy, fluctuating sex hormones, this will produce messy, unreliable data that is not very applicable to males.

So, it's because of the menstrual cycle and the sex hormones that scientists decided long ago it would be far more sensible to only study males and then just assume that this knowledge will apply to females because, and here's the kicker, females aren't that different to males, so it shouldn't matter too much. Absolutely winning logic from the finest minds of our times. So here is my message.

We need not be fearful of sex hormones. If there was greater appreciation for these incredible workhorses of the human body, scientists would not be so apathetic about the value of studying females. The problem is we're so myopic in how we think about sex hormones.

Scientists think unless they're studying reproduction, they can safely ignore sex hormones and ergo women. But sex is just one of the many roles that sex hormones have in our bodies. Even the scientists who discovered sex hormones warned against calling them sex hormones because it might incorrectly imply that sex is all these hormones do, when the truth could not be further away.

The most powerful organ that our sex hormones influence is not our genitals. It's our brains. Our brains are crawling with sex hormones.

And as our brains influence all aspects of our thoughts, our feelings, our behavior, this means that sex hormones influence all aspects of what it is to be human. And it turns out that estrogen, that much maligned hormone that throughout history has been blamed for everything from hysteria through to causing crops to wither and die, well, estrogen may be the key to health, happiness, and longevity.

Estrogen is neuroprotective, meaning it's responsible for keeping your brain healthy. If you get a brain injury, estrogen will reduce inflammation and stop further brain damage. Estrogen is also essential to our immune function. The enormous hit of estrogen that you get during pregnancy can actually reduce symptoms of autoimmune conditions like MS and rheumatoid arthritis.

Estrogen increases serotonin, dopamine, those happy neurotransmitters, and helps our brain regulate unpleasant emotions like anxiety and depression. High levels of estrogen throughout the menstrual cycle, rather than making us hormonal and erratic, actually alleviate symptoms of conditions like anxiety, depression, even schizophrenia. On top of this, we've found that anxiety treatments are much more effective if you deliver them during menstrual phases when estrogen levels are high, like ovulation, rather than low, like menstruation.

Unfortunately, we've also found that women taking the hormonal contraceptive pill benefit the least from anxiety treatments, and this is because the pill chronically suppresses our body's natural estrogen, which our brains need to reduce anxiety. Of course, when scientists were developing the pill, they weren't interested in its effects on our brains, but as anyone who has gone through menopause will appreciate, estrogen is the superpower that keeps our brains and our bodies running. Imagine the progress we could make, the lives we could improve, if we just started including females in research and learnt more about how we can harness estrogen's superpowers.

Now, men, you've been very patient.

Laughter

Lest you feel left out, let me bring you into this conversation, let you in on a little secret. You've got sex hormones too.

Of course, we all know about testosterone, but did you know that testosterone is also volatile? Women's estrogen fluctuates over the course of a month. Men's testosterone, I hate to tell you, but that thing is fluctuating on a daily basis. That's right, it starts out high in the morning and then drops down over the course of the day and then increases again at night and starts the whole cycle over every single day.

Good God, men, it's a wonder you're not a blithering mess.

Laughter

Maybe we should rethink your right to stand in Parliament or to be included in the scientific evidence base. Oddly enough, those propositions have never been put forth by the bearded men, I mean the scientists and politicians who make those decisions.

Anyway, the bigger part of the secret is that estrogen, women's superpower, you've got it too. And not just a little, a lot. You see, most of testosterone's actions on the brain only happen after it's been converted into estrogen.

And your brains can make new estrogen whenever it needs to. So, while you don't have a lot of estrogen circulating around your body, you've got a hell of a lot of it in your brain, that thing that makes you human. And what do you use all this estrogen for, you might ask? Everything.

Those superior map reading skills you're well known for.

Laughter

Wouldn't have those without estrogen. You see, the hippocampus, the part of the brain that's responsible for map reading, is absolutely loaded with estrogen.

The hippocampus is also responsible for learning and memory, which means that every time you're forming a new memory, like right now as I'm speaking, your brains are producing new estrogen, which is helping you encode this memory and store it for the long term. Why you would not remember a single thing if you didn't have estrogen. And this has led researchers to think that estrogen could be really important in the treatment of dementia, in both men and women.

But the irony is we would never have made these discoveries about men if we hadn't included women in research in the first place, which alerted us to the fact that estrogen is kind of a big deal. So, men, our knowledge about your health is also compromised by our failure to include women in research. And if we can't get the fundamentals of sex studied, how do we even begin to consider gender? Innate variations in sex characteristics, sexual orientation, all factors that significantly impact our health prognosis and our interactions with health services.

If you're feeling angry right now, I stand with you. So, what are we all going to do about it? A good place to start is at the dinner table. Talk to your family and friends about the sex bias in medical research. Extend that conversation to your co-workers. Ask your GP or your physiotherapist if their treatment has been shown to be evidence-based for your sex. And then when you're tired of talking, adopt another one of women's superpowers and start nagging.

Laughter

Nag our federal MPs to establish an Australian mandate that females must be included in all Australian medical research. Nag your daughters to have careers in science so that they can say what are the important questions to ask? Because at the end of the day, girls just want to see their clitoris on the pages of Grey's Anatomy. Go Helen!

Applause

UNSW Centre for Ideas: Thank you for listening. This event is presented by the Festival of Dangerous Ideas and supported by UNSW Sydney. For more information, visit unswcentreforideas.com and don't forget to subscribe wherever you get your podcasts.