According to work done by social researcher Nelly Oudshoorn, now based at the University of Twente in the Netherlands, hormone research sent waves of excitement through the pharmaceutical industry in the 1920s. Suddenly, here was a way of scientifically understanding masculinity and femininity. With some effort, drug companies believed they could isolate and industrialise the production of sex hormones to make people more masculine or feminine.
Endocrinology – the new and controversial study of hormones – was turning into big business. Tonnes of animal ovaries and testes were harvested, and thousands of litres of horse urine collected, as scientists desperately searched for the chemicals that defined what it meant to be male or female. The director of Dutch pharmaceutical company Organon described the process of isolating hormones as ‘finding gold in the urine of pregnant mares’.
By the end of the decade, treatments based on sex hormones were becoming available, and there appeared to be no limit to what they promised. In the archives of London’s Wellcome Library, which keeps an enormous trove of historical medical documents, I find an advertising pamphlet from around 1929, produced by the Middlesex Laboratory of Glandular Research in London. It proudly announces that it’s finally possible to replenish the ‘fire of life’, to cure impotence, frigidity and sterility in men using ‘the therapeutic utilisation of the sex hormones of fresh glands removed from healthy animals, such as the bullock, ram, stallion, ape’. Treatments containing oestrogen made similar claims aimed at women, promising to cure irregular periods and symptoms of the menopause.
Of course, hormone treatments couldn’t possibly live up to all this hype. But they weren’t just a fad either. They really did seem to work for certain symptoms, even if the evidence was only anecdotal. An article in the Lancet in 1930 reports a male patient who had been given testosterone saying that he thought ‘his muscles were firmer and he felt more pugnacious; he nearly had a fight with his workmate’. Another man, aged sixty, was able ‘to play thirty-six holes of golf in a day without undue fatigue’. Testosterone became associated with what were believed to be manly qualities, such as aggression, physical power, high intellect and virility.
The same research was done on women using oestrogen. Another article in the Lancet in 1931, the researcher Jane Katherine Seymour has noted, connected the female hormones to femininity and childbearing. Under their influence, it also said, women ‘would tend to develop a more passive and emotional, and less rational, attitude towards life’.
In the very early days of endocrinology, assumptions about what it meant to be masculine or feminine came from the Victorians. With the discovery of hormones, scientists had a new way to explain the stereotypes. According to Anne Fausto-Sterling, professor of biology and gender studies at Brown University, Rhode Island, the prominent British gynaecologist William Blair-Bell, for instance, believed that a woman’s psychology depended on the ‘state of her internal secretions’ keeping her in ‘her normal sphere of action’. At that time, this meant being a wife and mother. If she stepped outside these social boundaries, scientists like him implied it must be because her hormone levels were out of whack.
In other words, according to researchers, sex hormones were doing more than just affecting reproductive behaviour. They were responsible for making men manlier, by the standards of the time, and women more womanly, again by the standards of the time. Reasoning in this way, scientists assumed that the sex hormones belonged uniquely to each sex. Male hormones – androgens – could only be produced by men, and female hormones – oestrogen and progesterone – could only be produced by women. After all, if they were the key to manliness and womanliness, why would it be any other way?
An interesting experiment in 1921 hinted at the possibility that all the assumptions scientists were making about sex hormones might be wrong.
A Viennese gynaecologist revealed that treating a female rabbit with an extract from an animal’s testes changed the size of her ovaries. Later, to their shock, scientists began to realise that there were significant levels of androgens in women and of oestrogen in men. In 1934, the German-born gynaecologist Bernhard Zondek, while studying stallion urine, reported on ‘the paradox that the male sex is recognised by a high oestrogenic hormone content’. In fact, a horse’s testes turned out to be one of the richest sources of oestrogen ever found.
Just when endocrinologists thought they were getting a grip on what sex hormones did, this threw everything into confusion. And it raised an interesting dilemma: if oestrogen and testosterone determined femaleness and maleness, why did both sexes naturally have both? What did it even mean to be born male or female?
For a while, some scientists thought that female sex hormones might be turning up in men because they had eaten them. This bizarre ‘food hypothesis’ was ditched when it gradually became clear that male and female gonads can in fact produce both hormones themselves. Others then thought that the only thing oestrogen could be doing in a man was pulling him away from masculinity and towards femininity, perhaps even towards homosexuality.
It took a while for scientists to accept the truth: that all these hormones really did work together in both sexes, in synergy. Nelly Oudshoorn has described how important a shift this was in the way that science understood the sexes. Suddenly a spectrum opened up on which men could be more feminine and women more masculine, instead of simply opposites. Writing in 1939, at the end of what he described as this ‘epoch of confusion’, Herbert Evans at the Institute of Experimental Biology at the University of California, Berkeley, admitted, ‘It would appear that maleness or femaleness can not be looked upon as implying the presence of one hormone and the absence of the other … though much has been learned it is only fair to state that these differences are still incompletely known.’
The implications of this change of thinking were spectacular. The entire notion of what it meant to be a woman or a man was up for grabs. Researchers in other fields began to explore the boundaries of sexual and gender identity. The American cultural anthropologist Margaret Mead started writing at around the same time about masculine and feminine personalities, and how culture rather than biology might be influencing which ones people had. Studying Samoan communities in 1949, she wrote, ‘The Samoan boy is not over pressured into displays of manhood, and the girl who is ambitious and managing has plenty of outlets in the bustling, organised life of the women’s groups.’ The Mundugumor tribe of Papua New Guinea, she also noticed, created women with more of a typically male temperament.
Not everyone today agrees with Mead’s observations, but her ideas did signal how society was changing, in part prompted by science. There was a radical move from the old Victorian orthodoxies of the kind to which Charles Darwin had subscribed. People could no longer clearly define the sexes. There was overlap. Femaleness and maleness, femininity and masculinity, were turning into fluid descriptions, which might be shaped as much by nurture as by nature.
This revolution in scientific notions of what it meant to be a woman came in time for the second wave of feminism in the 1960s and 1970s, following the pioneering movement decades earlier that had earned women the vote. By now, female biologists, anthropologists and psychologists were entering universities and graduating in growing numbers. They were becoming researchers and professors. This helped research on women to enter another era. Fresh ideas challenged long-standing narratives.
The path paved by Eliza Burt Gamble, the pioneering suffragist who had dared to challenge Charles Darwin in the previous century, was being trodden by a new generation of scientists.
We arrive at today.
Lingering stereotypes about sex hormones remain. But they are being constantly challenged by new evidence. According to Richard Quinton, common assumptions about testosterone have already been shown to be way off the mark. Women with slightly higher than usual levels of testosterone, he says, ‘don’t actually feel or appear any less feminine’.
In 2008, former Wall Street trader John Coates, a neuroscientist at Cambridge University who researches the biology of risk-taking and stress, decided to see whether the cliché of stock-market trading floors being testosterone-fuelled