Intrusive visual inspections began to be used to detect male impostors at major sporting events, but from 1968 these were replaced by various tests that verified a female competitor's physiological sex by not detecting the presence of either a "male" XY chromosomal pattern or a Y gene. 

Whilst the introduction of genetics based testing for female athletes seemed to make a lot of sense at the time, it unfortunately soon became clear that the majority of the "fails" were athletes who due to a medical disorder had a Y chromosome but were otherwise undoubtedly female in both gender and secondary sexual characteristics.  Failing a "sex test" was a traumatic event for some of these women, e.g. Sarah Gronert reluctantly retired from professional tennis after intense 'changing room' pressure from her peers when it became known that she was gentically male (XY).  This was despite the fact that she is legally a woman, her body is externally completely female, and male hormones have no effect due to a medical condition.

Sport and Transwomen
Since the 1970's discrimination against male-to-female (MTF) transsexual women has become increasingly unacceptable - both legally and socially. 

It seems reasonable that if a MTF transsexual is living as a woman, is legally a woman, has a passport stating 'sex: female', and is perhaps married as a woman - then she should be able to compete in sports as a woman.  But some people - even some transsexual women - have severe reservations about the fairness of allowing this, particularly if little or no medical treatment has been given. 

Renée Richards

For example, if the world record holder of the men's 100 metres race legally transitioned to female and then also set a new women's world 100 metres record - should that really count?  This type of scenario suddenly became a real possibility when in 1975 a 6 ft 2 inches tall, 40 year old, American eye surgeon and amateur tennis player called Dr Richard Raskind had SRS and became Renée Richards.  After a legal fight, in 1977 she won the right to compete in women's professional tennis.  In 1978 she reached the women's quarter-finals of the US Open tennis championship and in February 1979 - at the age of 44 (seven years older than any other woman in the top 100) - was ranked the 20th best female tennis player in the world.  Even Renée subsequently expressed doubts about the fairness of this.

Transsexual Australian / Danish golfer Mianne Bagger

Another factor - if rarely openly mentioned - is that women's sport has become financially very lucrative.  For example, in 2021 the Ladies European tour offered prize money of €20 million that year, and the USA LPGA tour nearly five times as much.  Top 10 female golfers earn at least $1 million a year in prize money, endorsements and sponsorship deals.  By comparison, a professional male golfer ranked 250 - 1000 will barely earn enough to pay his expenses, but as a woman can earn multiples more.  Denmark born golfer Mianne Bagger is sometimes (very unfairly) quoted as example of this potential problem.  After moving to Australia, she had SRS age 19 and subsequently never hid the fact that she was transgender as she progressed from an amateur golfer to becoming a professional female golfer in 2003.  She then had considerable sporting success and was the first openly transgender woman to compete in top ranking events such as the Women's British Open and the US Women's Open.  Canny investment of her prize money resulted in her being worth $82 million by 2019!

It's Physical
Experts have been saying that women are rapidly closing the performance gap on men in sports, and some studies even optimistically claim that women could overtake them in the future (e.g. "Will Women Soon Outrun Men?" by Brian Whipp and Susan Ward, Nature, 1992).  But the the brutal reality is most men are still taller, heavier, faster, stronger, bigger, and more powerful than most women, and are likely to remain so.  A study in 1997 by Seiler and Sailer published in Sportscience News found a male-female performance difference of 11-12 percent.  This was controversial at the time, but the table of World Record's given in table at the top of this page has very similar differences.

There is no doubt that the difference in male/female physical performance is best explainable by the substantial list of physical differences between men and women - even if we only consider factors directly related to sports.

Males typically have greater bone strength and density, greater muscle bulk and broadness in the shoulder area, and greater subcutaneous fat in the upper half of the body.  At maturity, females are generally shorter in height, have more flexibility in their joints, have more delicate ligaments and tendons, have more subcutaneous fat in the hips and lower body regions, have less erythrocyte and haemoglobin mass (which directly affects the ability to of the blood to carry oxygen and get rid of carbon dioxide), and exhibit a greater degree of pelvic tilt and obliquity.  The female elbow offers a greater carrying angle and tendency toward cubitus valgus (i.e. the lower arms stick out more), and the female has smaller lungs, heart, liver, and kidneys than the male.  Female joints are more subject to injury in sports requiring an expulsive effort, sudden stopping, sudden checking of speed and turns, and landing in jumps.  These differences are partly to the man's X chromosome, and partly due to the fact from about age 13 the bodies of boys are powerfully influenced and "masculinised" by a flood of testosterone from their gonads, while simultaneously the growth of girls is actually limited and "feminised" in a more delicate direction by the flood of oestrogens from their ovaries.

1.  Lungs and Blood Adult men have lungs 20% larger in capicity than women, and haemoglobin levels about 12% higher
2.  Muscle Males have more muscle in upper bodies, while females have more in lower portion
3.  Height Men are on average bigger and taller
4.  Longer limbs Men have a longer lever arm, meaning more force exerted
5.  Bone density Higher in men due to testosterone levels
6.  Wider pelvis Female skeletons load weight onto the knees, increasing the chance of injury
7.  Joint flexibility Oestrogen levels enable women to be more flexible
8.  Breasts Restrict chest muscles  

A rare exception has been Joanna Harper - a medical physicist in Portland, Oregon - who conducted research into the effect of testosterone blockers on transgender women runners like herself.  In 2015, she published the first study of transgender women and athletic performance and found that trans women ran at least 10 percent slower after beginning hormones. And, relatively speaking, they did no better against cisgender female runners than they had previously done against cisgender men.

A very influential study by Roberts, Smalley and Ahrendt was published in 2020.  This compared the physical performance in annual fitness tests of 46 young transwomen who transitioned (average age 26) and began hormone therapy such as oestrogen whilst serving in the USAF, with the average performance of about 200,000 cis- service women under age 30.  On average, the transwomen had been on hormone therapy for 2.5 years at the time of their third and final test.  The study concluded:

• Transwomen retain an advantage in upper body strength (push-ups) over female controls for 1–2 years after starting gender affirming hormones.

• Transwomen retain an advantage in endurance (1.5 mile run) over female controls for over 2 years after starting gender affirming hormones.

• Transwomen are currently mandated to have 1 year of testosterone suppression before being permitted to compete at the elite level. This may be too short if the aim is a level playing field.

Roberts, however, suggested the difference in running times needs additional perspective. "It was a 12% advantage after two years in run times. But to be in the top 10% of female runners, you have to be 29% faster than the average woman. And to be an elite runner, you've got to be 59% faster than the average cis woman."

The table below shows the relative advantage that a genetically XY transsexual woman may have in sports over a genetically XX cis-woman.  It is rather speculative but is supported by the limited research available.  For example, one study found that androgen deprivation in MTF transsexuals increases the overlap in muscle mass with women but does not reverse it.

Sex Testing
As described above, a man competing as a woman would in many sports have arguably an unfair advantage.   It is possible that ever since competitive sports began there have been suspicions that some of the female competitors were not actually women - but the reality is that female sporting events weren't considered very important until the 20th century. 

The potential scale of the men-competing-as-women problem first became apparent after the 1932 and 1936 Olympic Games. 

At the 1932 Olympics the Polish sprinter Stanisllawa Walasiewicz (later Stella Walsh) was the winner of the women's 100-meters , but the IOC recovered her medals after learning that she had male reproductive organs. A post-mortem in 1980 revealed that she had male genitalia as a result of a rare genetic condition called mosaicism. 

Even worse, the German high jumper Dora Ratjen came fourth in the 1936 games.  In 1938 it emerged that "she" was actually a transvestite man called Hermann Ratjen, and unlike Stella he/she had no medical condition as explanation.  The IOC was further worried to learn that three other track-and-field champions who competed as females in the pre-WW2 games eventually underwent reconstructive surgery to remove external, male-like reproductive structures.

After WW2, sport became increasingly super-power politics by other means.  The masculine physique, deep voices and facial stubble of some formidable Eastern bloc "female" competitors became impossible to ignore, and after the 1964 Olympic games. it was decided to introduce sex tests.

Sex testing officially began at the 1966 European Athletics Championships in Budapest.  This was a simple visual exercise - women competitors were required to disrobe so that medical staff could "peak and poke" their genitals to decide whether they were indeed a woman.  Of course, many female competitors found this offensive, but it was also quickly obvious that several dozen athletes were not attending events where sex testing was being conducted.  The most prominent absentees were the Press sisters Tamara and Irina from the Soviet Union - who between them won five Olympic titles in the shot-put and hurdles respectively in the early 1960's.

The quality of sex reassignment surgery (SRS) was rapidly advancing and it was quickly realised that after SRS a former man could pass the "peak and poke" test as a woman.  Therefore the far more sophisticated polymerase chain reaction (PCR) buccal smear test was introduced to examine the competitors chromosomes - with the blunt rule that if they weren't XX she couldn't compete as a woman.  Ewa Klubukowska, a 1964 sprint bronze medalist for Poland, had the dubious honour of being in 1967 the first woman to fail the sex test on account of possessing an XXY chromosome pattern, although she was clearly female in every other way.  "I know what I am and how I feel" she said at the time.  Soon after Ewa failed her "female" sex test she became pregnant and in 1968 gave birth to a healthy boy.  However, on on the other side of the coin Austrian skier Erika Schinegger (Women's World Downhill Champion in 1966) decided to become Erik after failing her sex test and later fathered a daughter.  Ewa and Erika were in crowded company at the time, as many other female athletes, including five British athletes, failed the new sex test in its early days. 

Complete AIS is sometimes presented as the ultimate form of male-to-female transsexual - the suffer is genetically male XY but has a completely normal female body (albeit lacking internal reproductive structures) due to the total inability of their bodies to use the male androgen hormones produced by their testes in anyway, including for muscle development or VO2max.   However, a very interesting paper, "Complete Androgen Insensitivity "Syndrome": A Model For Human Performance in Sports," does not fully support the view that AIS women - or indirectly male to female transsexuals - have no advantage in women sports.

The 1968 Olympics was the first to require sex testing, and from the start the fairness of this gender verification test was hotly disputed as the vast majority of the women who failed suffered from Complete AIS (CAIS).  They had a female birth certificate so were legally female, and regard themselves as women.  Whilst pumping women athletics full of male hormones was almost certainly a common practice in the Soviet block until this date, it wouldn't work with an AIS woman.  "It’s sheer lunacy to think that an AIS woman has an advantage in sports," explains Sherri Groveman, who helps runs an AIS and intersex support group "In fact, we’re somewhat at a disadvantage.  I could be taking steroids all day long, and unlike other women I wouldn’t develop increased muscle mass.  My body can’t respond to androgens."

[Without wanting to argue with Ms Groveman, I do wonder if a skeletal advantage explains at least some the exceptional success of AIS women in the sporting field.   For example, the average AIS woman is in the top 10% of the overall female population in terms of height, is it then only a co-incidence that AIS women greatly over succeed at the top level of women's sports?]

Things came to a head with the Spanish hurdler Maria Jose Martinez Patino.  She suffered from AIS, i.e. had male XY genes, but in 1983 she mistakenly passed a sex test and was certified as XX female.  However the 24-year old was retested when she entered the 1985 World University Games in Kobe, Japan.  On the way to her first race, she was told that she was genetically male and should fake an injury and withdraw (apparently a common practice when a sex test was failed) - if she didn’t it would be leaked to the press that she was a man.  She didn’t back down and she won her race.  The next day, her story was front page news.  She returned to Spain to be stripped of her titles and lost her university scholarship and her boyfriend.  Patino told a reporter “I knew I was a woman in the eyes of medicine, God, and, most of all, in my own eyes ... If I hadn’t been an athlete, my femininity would never have been questioned". 

Between 1972 and 1984, thirteen women failed the Olympics' chromosome test and were barred from competing.  Like Maria Patina, the vast majority were still women that suffered from partial or complete Androgen Insensitivity Syndrome.  The Olympic Games Organising Committee started to face huge pressure from that "false positives") were ruining the lives and careers of some women athletes.  Exemptions began to be made, starting in the 1988 games with Maria Patino!

However genetic testing continued, and this still affected many female athletes:

• In the 1988 Summer Olympics in Seoul an unnamed top women's tennis player was prevented from competing when her AIS condition was identified. 

• In the 1992 Olympics in Barcelona 5 out of 2,406 women tested as genetically "male", all with some form of AIS. 

• In the 1996 Olympics in Atlanta 8 women out of 3387 didn't pass as female - 4 with cAIS, 3 with pAIS and 1 with another condition (5-alpha-reductase deficiency).  6 of the 8 had had surgery to remove their gonads.  All were allowed to compete. 

Between 1972 and 1990, one in every 504 elite female athletes was found ineligible as a result of sex chromatin testing yet not one was found to be a "normal male".  Almost all the disqualified athletes suffered from AIS, but only about 1 in 3500 women suffer from the syndrome.  An interesting corollory is thus that a genetically XY woman with AIS is roughly seven times more likely to become an elite female athlete than an XX cis-woman.

If AIS women do have a physical advantage in sports then it probably lies in the fact that they often tend to be taller and their skeleton closer to male than female in structure, although their musculature and body fat distribution is female.  For example Sarah Gronert - who has AIS and had genital surgery age 19 - lacks the robust skeletal frame and muscular appearance induced by decades of testosterone that caused Renee Richards so many problems in the 1970's.  However, and unsurprisingly, Sarah's best world ranking on the women's tour was 164 (age 26) whilst Renee reached 20 (age 46).  There's considerable competitive interest in this association as it has been suggested that Complete AIS represents a valuable model for female performance in sports.

By the early 1990's the whole costly process of sex testing was becoming far more trouble than it was worth as it had become obvious that blatant cheats (i.e. a man with out surgery trying to compete as a woman) could be easily picked up by other means.  The vast majority of failures to pass the "sex test" were still due to AIS and no one was now arguing that AIS women were not women, so in effect most of the results were effectively false positives.  It was clear the effects of illegal performance enhancing drugs such as steroids and testosterone on the genetically XX female body were far more significant than an athlete suffering from AIS.

Finally in February 1999, the Athletes' Commission of the International Olympics Committee urged its parent organization to do away with sex analysis entirely and rely instead on observed urination during drug testing to pinpoint any obvious male impostors. 

A New Era

Erika Coimbra at the Sydney Olympics.

Mandatory sex testing for women was abandoned for the 2000 Sydney Olympics, but this arguably led the media to search hard for examples of competing female athletes who may have failed the test.

Considerable press coverage was given to two Brazilian women - Judo competitor Edinanci Silva and volleyballer Erika Coimbra - when it was leaked to the press that both were born hermaphrodites, with non-functioning male genitalia which had been surgically removed.  It was confirmed by the IOC that both suffered from AIS and were eligible to compete as women, but sadly spectators and even some of their opponents made it known that they were unhappy about this fact.  The attractive looking Erika (age 20, weight 64kg, height 180cm, with long blond hair) received far less abuse than the much plainer looking Edinanci (age 24, weight 71kg, height 175cm), whose opponents disgracefully started to refer to as "he". 

In February 2004 an  IOC advisory group recommended that individuals undergoing sex reassignment after puberty could compete in the Olympics, but only under certain conditions:

• Surgical changes must have been completed, including external genitalia changes and removal of gonads.

• Legal recognition of their assigned sex must have been conferred by appropriate official authorities.

• Hormone therapy -- for the assigned sex -- must have been given for long enough to minimize any gender-related advantages in sport competitions, a period that must be at least two years after gonadectomy.

On Monday, 17 May 17 2004 the International Olympic Committee announced  - albeit with some mixed reactions - that it was dropping all sex testing for woman's sports.  Transsexuals passing the prescribed conditions were also cleared to compete in the Olympics by the IOC Executive Board.  The  IOC spokeswoman Giselle Davies said the situation of transsexuals competing in high-level sports was "rare but becoming more common."  IOC medical director Patrick Schamasch said no specific sports had been singled out by the ruling.  "Any sport may be touched by this problem," he said. "Until now, we didn't have any rules or regulations. We needed to establish some sort of policy."

The decision, which covered both male-to-female and female-to-male cases, went into effect starting with the Athens Olympics in August 2004.  The new rules allowed the classification as female all men who had undergone a SRS operation, regardless of whether this was before or after their puberty.

Renee Richards (who has some regrets about her own transition and SRS) believes that it all comes down to fairness.  Renee would bar transsexuals from women's sports if they were in their 20s and still had muscular male physiques that gave them an advantage over other women:

"That's why we have junior events and senior events, men's events and women's events, and why 130-pound fighters don't fight against 180-pound fighters.  We have categories in sports to have level playing fields.  Tiger Woods or Jimmy Connors or John McEnroe, if they're 25 years old and they have a sex change and within the next five years they go out to play against women, of course they have a great advantage.  

Renee also warned that unscrupulous male competitors could use the IOC's 2004 rules to give them more chance of success, albeit by competing in women's events.

"It's ironic that everyone has tried so hard to keep a level playing field - from corked bats to doping - but now the IOC has come up with a decision that defies fairness in a similar vein.  Sex-reassignment surgery is based on putting materials into your body."

Putting things in a UK context, the new reality was that Tim Henman could become Tina Henman and would probably thus become a [female] Wimbledon champion at last.  With Henman’s strength and speed, height and muscle density, added to his skills, it would be a near certainty even after a year of female hormones and aging.

A counterview to Renee is offered by Alisha Kia Siadeski (formerly Paul), a trangender 'cowgirl' whose title winning passion is barrel-racing - a minor women-only sport.  She says: "I'm 5'5" and weigh 112 pounds - I have no strength advantage, never did ...  half the women I compete against are bigger and stronger than I am".   

Indeed, in 2007 Renee herself argued against the theory that desperate athletes will do anything to win the gold, even change their gender.

"How hungry for tennis success must you be to have your penis chopped off in pursuit of it? .... It's unlikely there will be a rush of men ... switching sex to clean up on the women's tour. Those fears are silly"

There was no rush by male athletes to compete as a woman and it began to seem that sporting world had reached a generally acceptable compromise ... and then Caster Semenya burst onto the scene.

Doubts Begin To Return

A junior champion in 2008, the South African teenager took seven seconds off her personal best for 800m over the next nine months, breaking the South African record and setting a world-leading time in the process. The International Association of Athletics Federations (IAAF) felt "obliged to investigate", if only to rule out doping.  Hours before the start of the 800m final at the 2009 World Athletics Championships - a race Semenya would win by a huge margin - it was leaked that the sport's governing body had also asked for a gender test. The findings of the test were never released but she was cleared to compete again in women's athletics.   However CIS-female athletes increasingly complained that Caster had an "unfair advantage" over them. 

This triggered renewed reservations at governing bodies such as the IOC as to the extent to which women's sports should be open to transwomen.  The reservations focussed on androgenic hormones - the best known being testosterone which helps to form male characteristics such as strong muscles (except in AIS women). 

An IAAF working group, in conjunction with the IOC's Medical Commission, decided that female athletes with more than 10 nanomoles of Testosterone per litre (nmol/L) of blood would be bared from competition unless there were "reasonable grounds" for an exemption.  The AIS condition being an example. 

In April 2011, the new rules came into force. From this moment on, a confidential investigation could be made into any athlete where there were "reasonable grounds". This could be a complaint from a rival, or as a result of an anomaly in a drugs test.

Caster passed the revised tests and was able to compete as a woman at the Olympics, indeed she was chosen to carry her country's flag during the opening ceremony of the 2012 Summer Olympics in London.   Caster easily won the women's 800 metres races at both the London 2012 and Rio 2016 Olympics.  

 
Former male Olympic decathlon champion Bruce Jenner reappeared as female Caitlyn Jenner in 2015

Acceptance of Trans-Athletes

In the London Olympics of 2012, four female athletes with AIS were identified and allowed to compete - as had now become the long accepted norm.  The OIC also allowed an unnamed transgender/intersex athlete to compete as a female gymnast, however it bared transwoman Keelin Godsey from representing the USA in the women’s hammer throwing competition.

In January 2016 the International Olympic Committee issued recommendations that transgender athletes should be allowed to compete at the 2016 Rio Olympics without undergoing sex reassignment surgery.  Male-to-female transsexual athletes would only need to prove that their testosterone level had been below a cut-off point (set at 10 nmol/L per litre) for at least one year before their first competition.

The new guidelines - which the IOC claimed had been brought in to adapt to current scientific, social and legal attitudes on transgender issues - were not fixed rules or regulations but were instead designed as recommendations for international sports federations to follow.  

Former IOC medical commission chairman Arne Ljungqvist, who was among the experts involved in drafting the new guidelines, said:

"It has become much more of a social issue than in the past.  We had to review and look into this from a new angle. We needed to adapt to the modern legislation around the world. We felt we cannot impose a surgery if that is no longer a legal requirement."

Under the previous IOC guidelines of 2004, athletes who transitioned from male to female or vice versa were required to have reassignment surgery followed by at least two years of hormone therapy in order to be eligible to compete in their reassigned sex.  

The 2016 Olympics saw widespread claims that the Hungarian swimmer Zsuzsanna Jakabos was transsexual, but this was a fake news story - she had passed numerous sex tests since first appearing in the 2004 Olympics.  A report in the the Daily Mail newspaper that two British female athletes in the country's 2016 Olympics team were transgender was undermined by a complete lack of detail. 

Chloe Psyche Anderson is transgender and played women's volleyball in the USA at college level.  By 2017 she had been on female hormone therapy for five years, which had reduced her testosterone levels below even female norms.  She was still pre-SRS when she wrote in May 2017:

"I never doubted I could be an athlete and transition. I just had to do extensive research prior to make sure I fit into the associations legally, but my body and I have had a long and frustrating relationship to say the least.  Having low doses of testosterone for a long time has made building up muscle much more of a challenge than [it is for] my teammates, as well as muscle recovery time. As a transgender athlete I have felt that I’ve been struggling to fight an uphill battle against stereotypes that I am physically superior to my teammates and that I’m not like them. While the physical superiority couldn’t be more false, the reality that I am very different than my teammates couldn’t be more obvious.  [But] I am myself, I don’t want to hide who I am to anyone.  Nobody should be put into a situation where they should feel ashamed or belittled for who they are."

Whilst it's very dangerous to generalise, Chloe seems to be a reasonably typical example of a undoubtedly transwoman in her teens or 20's who wants to participate in competitive sport.  And she makes a strong case as to why this should be allowed. 

The first two decades of the twentieth century may become seen as a 'golden age'  for transgender athletes.  Medical barrier after medical barrier has fallen.  Genetics tests once set an insurmountable barrier for transwomen, gender confirmation surgery still a high bar, but the testosterone level test is far more modest - and that is difficult to enforce except at an elite level,

Further, in the EU and many other countries, laws have been passed which recognize male-to-female transwomen as  being a woman - from marriage to pension rights ... to gender discrimination.  For example, in the USA the Ladies Professional Golf Association's requirement that players were “female at birth” had to be removed in 2010 after a transgender woman, Lana Lawless, successfully sued the tour in a Federal court, arguing that the rule violated California civil rights laws.

As a result of legal threats and changing social attitudes, many sporting bodies have given up trying to define who can enter their "male/men's" events and who can enter their "female/women's" events.  In order to participate in women's sports, medical requirements are now very rare and even documentary requirements such as a female passport or birth certificate uncommon. 

 

A Backlash Begins

By the early 2010's the culmination of decades of campaigning had led to almost all sports and governing bodies accepting transwomen as being women - and radical surgery (SRS/GCS) was now rarely required.  A reluctance to risk being called out for transgender discrimination meant that almost no one was still prepared to enforce sex specific rules in sport.   Essentially athletes had become free to compete as male or female by self-declaration of their preferred gender - whilst at the same time the number active trans athletes was growing rapidly and becoming significant - millions rather than thousand.  E.g. a 2016 study from the Williams Institute, estimated that 0.6% of adults in the USA identify as transgender, whilst 1% of UK school children were officially registered as trans in 2019.

Since the 1960's it had been assumed that the acceptance of transwomen in female sports would create the most problems at the elite or professional level, but in fact serious issues first began emerging at the ground roots and amateur levels.  The unintended consequences of allowing transwomen to freely compete in women's sports started a backlash against transwomen athletes - particularly those who have had little or no medical treatment.

Transgender woman Hannah Mouncey (right) plays Women's Australian Rules Football.  She claims that she is "treated like shit" by opponents, fans and even the Association.

One example is the Boston Marathon, arguably the most prestigious marathon in the world.  It's popularity means that the number of runners has to be capped, and this is done by means of minimum qualification times for the male and female marathons.  However the organizers no longer set any medical requirements for sex of athletes and there is a concern that the increasing number of transwomen entering the race is lowering the qualifying time and preventing cis women from competing.  For a cis-woman who has spent several years desperately trying to qualify for the Boston Marathon, losing out to a transwoman who has had no medical treatment and easily managed the qualifying time in their only prior marathon is understandably annoying.

Most sports still follow the guidelines which were drawn up by the International Olympic Committee in 2015, which allow trans women to compete in female sport if their testosterone levels are below 10 nmol/L per litre.  However in 2017 the IAAF commissioned research which found that female athletes with high testosterone levels had a "competitive advantage" of up to 3%.   In April 2018 the IAAF introduced new rules for female runners with naturally high testosterone that effectively required them to take medication to reduce their testosterone levels to under 5 nmol/L for six months before competing as a women in events from 400m up to the mile.

Transwoman and cyclist Rachel McKinnon (centre) celebrating a win.

A report published by the UK’s five Sports Councils in 2021 also found that key physical differences remained even after reducing testosterone to this limit, stating "there appears to be a retention of physical capacity in transgender people who suppress testosterone from male levels.  ... For many sports, the inclusion of transgender people, fairness and safety cannot co-exist in a single competitive model.”  The report also describes the extent of the competitive advantage between males and females - adult male athletes have on average a 10-12% performance advantage over female competitors in swimming and running events but this increases in jumping events and strength based events like weightlifting.  The OIC itself admitted in August 2020 that its guidelines were “not fit for purpose”.

The unsurprising result is that more transwomen are competing in women's sports at all levels with ever greater success.  Social media is increasingly filled with photo's of large and heavily built transwomen competing in various woman's sports with complaints that "it's not fair" that these are allowed to participate, and suggestions (hushed at first, but increasingly strident) that these are not "real women". For example, Rachel McKinnon claims that she received more than 100,000 hate messages on Twitter after she won the UCI Masters Track World Championship cycling title in October 2018.

Another example is the article below:

Parents Launch Petition after Transgender Athletes Place First and Second in Girls Track Championships June 18, 2018 Andraya Yearwood Two athletes who were born males placed first and second in state track championship events for high school girls, causing anger among other competitors and parents who say they had an unfair advantage over the girls. Terry Miller and Andraya Yearwood dominated Connecticut’s races, sweeping gold and silver medals with little competition and stirring outrage among fellow competitors. Miller placed first in both the 100-meter and 200-meter dash, while Yearwood placed second to Miller in the 100-meter dash, CBS Pittsburgh reported. Both Miller and Yearwood are biological males who identify as females. Neither has undergone surgeries or used hormone blockers to lower their testosterone to a level comparable to females. The Connecticut Interscholastic Athletic Conference allows athletes to compete according to their gender identity and implements no hormone testing, as regulatory bodies do at the university level.

Parents began a petition after transgirl Andraya Yearwood took first place in the women’s 100 meter dash for a second consecutive year, it soon gained hundreds of signatures.  “I think it’s unfair to the girls who work really hard to do well,” said another sprinter, Selina Soule. She explained that she doesn’t think it’s fair for boys who identify as girls to race together when boys are faster and stronger than girls.

In October 2019,  Cheryl Radachowsky, a mother of a high-school female athlete wrote an impassioned piece in the New York Post about how her daughter was among those being affected by a 2017 Connecticut state ruling that boys who subjectively identify as female could compete against girls.

“Since then, two biological boys have won 15 women’s track championships, titles held by nine different girls in 2016.  As a parent, it is gut-wrenching to know that no matter how hard my daughter works to achieve her goals, she will lose athletic opportunities to a pernicious gender ideology. A biological boy’s subjective sense of his gender doesn’t cancel out his physical advantage over girls.”

The Crisis Point
The IOC's decision in 2004 to allow post-SRS transwomen compete in women's sports seemed very progressive at the time.  Whilst it caused some mutterings of discontent from elite female athletes, the number of (known) transgender athletes was so low that this seemed a reasonable compromise.   There appearted to be to have so little impact on elite women's sports that the follow on decision in 2014 to lower the eligibility criteria for transwomen to just a testosterone level test was much easier to make. 

Lauren Hubbard "crushed" her opponents in women's weightlifting competition s in 2017-18.  Before transitioning, she had set several records in male categories as Gavin. Lauren competed for New Zealand in the Tokyo 2020 Olympics (held in 2021).  She was the first openly transgender woman to do so.

Unfortunately, the IOC failed to recognised the post-2000 explosion in the number of young people with gender identify disorders.  In recent years there has been a huge increase in the number of MTF transwomen who want to participate in female sports, and most sporting organizations now allow transwomen to compete in women's sports, indeed they would potentially face legal challenges in many countries if they didn't.  It takes only a small amount of research show that transwomen are now participating in women-only sports such as synchronized swimming, rhythmic gymnastics, softball, netball and lacrosse. 

Multiple studies have now found that MTF transwomen, regardless of hormones levels, tend to be bigger, stronger and faster than their cis-counterparts. We seem to be moving to the situation where transwomen will dominate some women's sports, the leading contenders being: weightlifting, track, wrestling, football, basketball, and mixed martial arts.  When a transgender weightlifter won (yet again) a competition, Deborah Acason, from the Australian Weightlifting Federation, said "We all deserve to be on an even playing field, it’s difficult when you believe that you’re not.  If it’s not even, why are we doing the sport?”

Will Thomas (left) set USA female swimming records after transitioning and competing as Lia (right).

Will Thomas competed for two years in the University of Pennsylvania's men's swimming team until November 2019 with modest success.  In 2020, age 20, he decided to take took a season off whilst transitioning to Lia Thomas.  Her subsequent re-emergence in 2021 as a member of UPenns female swimmer was spectacular.  She won a 1,650 yards freestyle women's event by 38 seconds (a full length!) and a 500 yards freestyle women's event by 14 seconds.  Lia set two USA female swimming records and was regularly close to world records for female swimmers.  She was about 5% faster than her closest female cis-competitor in the National Collegiate Athletic Association (NCAA) championships - an extraordinary difference!

Linnea Saltz (left) and June Eastwood

An opposite story faced Southern Utah University sprinter Linnea Saltz in early 2020.  Age 19, she was preparing to defend her 800 metres 'Big Sky' title when she learned that a male athlete - Jonathan Eastwood - at the University of Montana had transitioned and would now be running for their women’s team as June.  The Montana athlete had a personal best a huge 10 seconds lower than Linnea's 2 minutes 5 seconds, Saltz said she then realized that her season wasn’t going to be about her hard work, pain and sacrifice to be a champion, but about fairness in women’s sports being "stripped away right in front of me".

Some parents are understandably getting upset when they see their cis-daughter trying to compete physically with much bigger, heavier and stronger transgirls.  The parents of the girls who competed against Lia Thomas sent a letter of demand to America's National Collegiate Athletic Association (NCAA), urging the sporting body to alter its rules -  "At stake here is the integrity of women's sports," the parents wrote in the letter.  Another problem was Lia was pre-SRS and still had a male anatomy, whilst her teammates were urged by the University to be supportive of Lia, they were reported as being uncomfortable about sharing the women's changing with her. 

When facing her critics, Lia claims to have lost a lot of muscle mass since starting puberty blockers and hormones.  She points out that she was much faster in 2019 when still competing as a male, e.g. 14:54:76 vs 15:59:71 in the 1,650 yards freestyle, and 4:18:72 vs 4:34:06 in the 500 yards freestyle. 

In March 2022 Lia become the first transgender person to win a women's NCAA Division I title, beating a 2021 Tokyo Olympics medallist in the 500-yard freestyle.  Her victory received an unusual reaction from other competitors.

 Similarly, the times June Eastwood ran on the University of Montana’s women’s cross country and track teams after a year of hormone therapy were lower than her times on the men’s team, whilst she was repeatedly close to breaking women's records he was not dominating competitions in the way that Lia was.  June decided not to run the 800m Big Sky race - which Linnea won - but she did enter and easily won the one-mile race. The parents of some transgirls also counter argue that their children are actually at a physical disadvantage in sports such as woman's artistic gymnastics, rhythmic gymnastics and figure skating - where a small and lightly built physique is very advantageous.

Hailey Davidson, age 29.

Golf has become another sport that is starting to doubt the wisdom of its 2010 decision to remove a 'female at birth' requirement in order to qualify for the Ladies PGA tour.  Several MTF transgender golfers have since achieved some success - e.g. Bobbi Lancaster and Mianne Bagger - but none have threatened to break in to the top level.  That almost changed with Hailey Davidson, who was born in Scotland but now lives in the USA.  She competed as a male golfer before beginning female hormone therapy in September 2015.  In 2021, after having SRS in January, she started (age 28) to compete in female golfing events with great success.  She was on the verge of becoming the first transwomen to qualify for a LPGA tour card when she unexpectedly failed to make the cut at the qualifying event in August 2022 - whilst she didn't blame 'anti-trans' spectators, some vocal jeers certainly wouldn't have helped her when making key strokes.

 

2022: Chaos and Confusion

Quinn competed for Canada in Woman's soccer at the Tokyo Olympics in 2021, winning Gold.

In Tokyo in 2021, the low barriers that the IOC has set finally resulted in the appearance of openly transgender women participating in female events.  It was originally stated that there three transwomen athletes had qualified for the Olympics, but four were named during the games - Rebecca Quinn (Canada, soccer), Alana Smith (USA, skateboard), Chelsea Wolfe (USA, cycling), Laurel Hubbard (New Zealand, weightlifting).  It was reported afterwards that nine transwomen had actually competed (albeit still just 0.16% of the 5,494 female athletes), implying that five were effectively stealth; their competitors being unaware that they were even competing against a transwoman.  Tokyo 2020 (actually held in 2021) also saw the award of the first woman's Olympic medal to an openly transwoman, Rebecca Quinn, who had outed herself in September 2020.

There is a widespread feeling that Tokyo 2020 effectively opened the floodgates, and many transwomen athletes such as Lia Thomas have their sights set on competing as women in the 2024 Olympics in Paris, France.  Also, a nation eager for Olympic medals could pack it's women's team with what are in reality men - far from theoretical given the way that some countries (most infamously  Russia in recent years) have systematically dosed their top female athletes with performance enhancing male testosterone hormones and steroids.

Historically, sporting bodies around the world have generally followed the lead of the IOC and IAA in regard to the recognition and acceptance of trans-athletes.  However, many began 2022 aghast at the impact that the new laisssez-faire approach was already having on competition at a grass roots level, with signs that this proceeding up to the elite level.

Emily Bridges, age 21.  She came out publicly as a transgender woman in October 2020 and had expected to be able compete in women’s events in 2022.

Cycling's ruling body, the UCI, became perhaps the first to act when on 16 June 2022 it tightened its eligibility criteria for the female category.  Cycling has become a very popular sport among transwoman, who enjoy considerable success at local levels in Canada, UK and the USA. This seemed likely to be repeated at the elite level when British transwoman Emily Bridges applied in March to compete at the British omnium championships in the women’s category.  This was blocked by the UCI at the last minute and British Cycling abandoned its own inclusion policy for transwomen shortly after.

Under the revised rules, the UCI lowered the testosterone limit from 5.0 to 2.5 nanomoles per litre, and doubled the length of time a trans-athlete must suppress her testosterone to within this range to two years. The UCI said that the maximum permitted plasma testosterone level value “corresponds to the maximum testosterone level found in 99.99% of the female population”.

Swimming was next up ... in early 2022 the USA Swimming governing body had reluctantly seized the cudgel as Lia's staggering success meant it had to act or lose all credibility with the vast bulk of its members.  In early 2022 it issued a policy which acknowledges that transgender participants may have "a competitive difference in the male and female categories and the disadvantages this presents in elite head-to-head competition".  Participants in women’s events now have to record low levels of testosterone for 36 months prior to competing, and they will be assessed to determine whether "prior physical development of the athlete as a male" gives them an unfair advantage.  For example, Lia's hands are estimated to have double the surface area of the average cis-female swimmer.  However, elements of this new policy were both subjective and subject to legal challenge.

The International Swimming Federation (FINA) decided that it was no longer possible or fair to allow national associations to "square the transgender circle", and a clear-cut rule was needed.  At its meeting on 19 June 2022 a proposed policy was distributed that stated that female transgender athletes can compete in the women's category "provided that they have not experienced any part of a male puberty beyond Tanner Stage 2 [which marks the start of physical development], or before age 12, whichever is later".  The full 24-page policy was only distributed 15 minutes in advance of the vote for fear that it would cause roars of outrage from trans-advovacy groups.  It was expected that policy would be almost unanimously approved by the 152 members of the association, so it was a shock when less than three-quarters voted in favour (71% in favour, 15% against, 13% abstained), although this was still sufficient for adoption.  It was suggested that whilst a number of European countries wanted the policy to be approved, their delegates abstained or even voted against it in order to protect themselves at a national level. 

The new policy effectively bans almost all MTF transgender athletes from competing in women's swimming events.  FINA will instead establish a new "Open" category in which transwomen can compete.  The policy has an exception allowing transgirls who have completed their transition by age 12 to compete as female, but this provision will cover only a tiny number of XY transgirls, and seems to be aimed at helping woman suffering from an intersex condition not recognised until early puberty.  Whether FINA can actually enforce the new rules, in particular at the Olympics, is again a moot point.  Within hours of the policy being approved, human-rights lawyers were openly discussing legal challenges, with a referral to the Court of Arbitration for Sport (CAS) probably being the first of many.

Transgender cyclist Rachel McKinnon (centre) has often been disappointed by the negative reaction of competitors to her wins but believes it's a "Human Right" to compete in her chosen female gender.

Extra-ordinarily, it was revealed on the same day (19 June) that the international governing body of association football (FIFA) had drafted new regulations to make it easier for transgender women to compete in female football/soccer competitions.  The new framework removes any testosterone threshold for transgender women, and proposes that footballers should be allowed to freely compete as their self-identified gender.

The next day, 21 June, Rugby decided to go in the opposite direction to Soccer, announcing that it had decided to preclude athletes who have transitioned from male-to-female from international competition. The IRL said in a statement that further consultation and research was needed before it could finalise its policy, but in the meantime, the ruling means that transwomen will not be able to play in Test matches or at the Women’s Rugby League World Cup. 

Finally, and potentially most importantly, on 22 June 2022 the World Athletics president, Sebastian Coe, hailed swimming’s decision to ban transgender women from elite female competition as being in “the best interests of its sport” – and hinted that track and field could soon follow suit.  He announced that the World Athletics council would also be reviewing its transgender and DSD (differences in sex development) athletes' policies at the end of the year.  Currently there are no transwomen in elite level track and field athletes, although CeCé Telfer became the first openly transgender person to win an NCAA title in 2019 in the women’s 400m hurdles.

 

A poster for a campaign against transwomen being allowed to compete in female sports.

Cycling - The Canary in the Mine

The debate about accepting transwomen as female athletes and sportswoman consistently focuses on athletics and swimming, with tennis and golf also often mentioned.  However, the sport that has actually been most been impacted by transwomen is undoubtedly cycling.  This article has already described the successes of Michelle Dumaresq and Rachel McKinnon. 

Cycling’s governing body, the Union Cycliste Internationale, has been at the forefront of attempts to allow transwomen to compete in female events.  In March 2020 it published rules based on IOC guidelines that allowed Male-to-Famele transwomen to compete in women events provided that their testosterone level had been below 5nmol/L for 12 months.  From 1 July 2022 this was revised to below 2.5nmol/L for a period of at least 24 months (a limit which 99.9% of cis women will meet), but unlike some other sports UCI didn't add the condition that the competitor must have transitioned by the age of 12 or before experiencing any stage of [male] puberty.

However, it

Tiffany Thomas, age 46, celebrates winning the Randall’s Island Crit Race in 2023.

 seems that in this sport the skeletal and respiratory advantages gained from a male puberty significantly outweigh the disadvantages due to taking female hormones after transition to female.  The sport has received a huge influx of transwomen who cycled recreationally as men, and post-transition discovered that they could compete in women's races at a near elite level.  For example, Tiffany Thomas won the Women's Randall’s Island Criterium ("Crit") race around parts of New York in March 2023 at the extraordinary age of 46, beating cis-woman half her age.  During the same weekend, at the USA Cycling National Cyclocross Championships in Hartford transgender Austin Killips finished third in the women’s elite race, with another transwoman finishing fifth.

Celebrating her victory on Instagram, Thomas said that she felt "like a superhero".  By contrast cis-female Hannah Arensman, who was fourth at Harford, announced her retirement from competition in the sport.  She said that it had “become increasingly discouraging” to train and then lose to someone with an “unfair advantage”.

Several women's cycling world records are now held by transwomen (e.g. Rachel McKinnon in the women’s age 35-39 sprint category) and the grass roots disruption and suspicion from allowing transwomen to compete is prevalent. Anytime a cycling event is now won by a woman who's above average in height and build, rumours are likely to start.

 

A Shock Decision
On 24 March 2023 the World Athletics Council, the governing body for international track and field athletics, made the shock decision to bar transgender women athletes from elite competitions for women.  It also tightened rules for athletes with sexual development disorders, cutting in half the level of testosterone athletes can have in order to compete in women's events.  A further surprise was that there was no exception for transwomen who transitioned at a very early age and didn't go through puberty as a male - although admittedly the numbers involved are very small and it would open up a potential loophole.

The Council said they ultimately decided to prioritize "fairness and the integrity" of the female competition over inclusion.  It seems that the Council was unconvinced that it was medically proven that genetically XY transwomen had no advantage over XX women in athletics, even with restrictions such as hormone levels.
"Decisions are always difficult when they involve conflicting needs and rights between different groups, but we continue to take the view that we must maintain fairness for female athletes above all other considerations," Sebastian Coe, the council's president, wrote in a press statement. 

Although the Council surprisingly claims that no transgender athletes currently competing in international track and field competition will be affected, if retrospectively applied it could affect several people who've won Olympic medals in recent games.

The World Athletics Council's decision will undoubtedly be legally challenged in many countries, and it remains to be seen if other sporting governance bodies such as the IOC will accept its decision and apply similar limits. 


What Next?

By 2020 the trans-positive bandwagon seemed to have gained so much momentum that opposition to transwomen competing as women appeared futile.

Renee Richards' 2007 famous quote of "How hungry for [sporting] success must you be to have your penis chopped off" no longer applies because such surgery is no longer required for a transwoman to be able to compete in woman's sports.  In recent years, the path for a middling male sportsman to become a top female sportswoman has become so easy that it may become a decisive consideration when considering whether to transition.  For example, the Gender Recognition Reform (Scotland) Bill allows anyone to self-declare their legal gender, without requiring any medical treatment and regardless of any prior documentation such as birth certificate or passport.  As such - if law is enacted (as of early 2023, the UK government is trying to block it) - men in Scotland can legally compete as a woman in any female sporting event by just signing a form stating that they are female.

Alessia Ameri was born Alessio in 1985.  A keen volleyball player he played for several Italian boys and mens teams, before transitioning age 30.  Since 2016 she's played for several womens teams and never encountered anything other than support from officials and other players, but the situation is changing ....

It was thus a huge surprise when in 2020 a study by the UK Sports Council's concluded that "For many sports, the inclusion of transgender people, fairness and safety cannot co-exist in a single competitive model”.  Since then, a vocal lobby to prevent or limit the participation of transwomen in female sporting events has unexpectedly emerged, but rolling back trans friendly rules will face legal challenges in many countries.  For example, some have passed laws that allow transwomen to obtain a replacement birth certificate stating that they are female, making recipients (regardless of their height, weight and build) almost impossible to refuse from entering women's sporting competitions. 

Renee, Kia and some sports organizations such as USA Swimming and the Women's Sports Federation seem to believe (albeit from an interpretation of their different approaches) that transsexuals should be evaluated on a case-by-case basis before being allowed to compete as women.  But there is then an implication that transwomen will have to be below a certain age, height, weight or strength before they are allowed to compete as women in a certain sport - and "discrimination" is a word that will inevitably be raised in court by someone that fail the tests.

I'm not sure what the answer is.  I agree that allowing adult men with no medical treatment to self-certify themselves as female and then be able to compete in women's sports against cis-woman is unfair to the later, whilst at an elite level it is now starting to distort results and records.  A few unsatisfactory alternative options for Women's sport federations whose competitions are becoming affected by the participation of transwomen include:

... since c.2020 there has been a huge push-back on the acceptance of transwomen as women in female competitive sports.

1. Limit competitors in female sports to those "born a natural woman".  This approach may be challenged and judged illegal in some countries.
2. Follow FINA's lead and introduce sporting events or categories that specifically exclude or include transgender individuals, e.g., with transwomen limited to an "open" category.  However, it seems unlikely that "open" categories will attract many entries - a transwoman aiming to beat the best cis-women in the world may be highly motivated, but the prospect competing against a few other transwomen in a fringe event will be of little interest.
3. Follow UCI's approach for cycling by imposing rigorous conditions on the participation of transwomen in womens events.  For example, by requiring that a transwoman is post-GRS, has cis-female levels of testosterones, and her physique is within three standard deviations (99.7%) of the global cis-female average.
4. Try to find legally acceptable ways of limiting some competitions and events to primarily cis women.  For example, it can be argued that requiring a competitor to have "XX" genes in order to enter a particular sporting event is a clear definition that is no more discriminatory than requiring competitors in an over-45's road race to prove that they are over the age of 45.

Sadly, all the options take us back to the situation that most transwomen faced before c.2004 - exclusion from competitive sport with genetically XX cis women at the highest level.

The 2024 Olympics in Paris has become a crux point - will MTF transgender women again be allowed to freely compete in women's events?  And if a genetically XY transwomen then sets a new women's world record, how credible will that be seen?  Quite probably an * qualifying the record will be added to history books.  An expected comprise is that the IOC will required any female athlete who is genetically XY to have transitioned before age 12, the age at which male puberty typically starts.  This will avoid any problem with women who suffer from consitions such as AIS, but prevent transwomen who have the potential advantage of a 'testosterone soaked' puberty from competing.

Looking further forward, it seems likely that in order to reduce potential legal problems, some of the minor sports that most obviously favour transwomen will simply be removed from the programme of sporting events.  Examples are Weight Lifting and Boxing, the inclusion of these in the Olympics has become increasingly controversial and they would be relatively easy to drop, perhaps as early as 2028.


Update 11 August 2024: The Paris 2024 Olympics

Ahead of the Paris Games, the IOC introduced the concept of differences of sexual development (DSD) and new rules and regulations relating to accepting to with DSD. The new IOC rules say that inclusion should be the default in such cases and that athletes with DSD should only be excluded from women’s competition if there are clear fairness or safety issues.

Imane Khelif consoling Angela Carini after their very short bout.

To say that the Paris 2024 Olympics' then proved to be controversial in regard to the eligibility of some participants in women's events is an understatement.  The focus particularly focused on two boxers, Imane Khelif from Algeria and Lin Yu-ting from Taiwan.  They respectively and very controversially won the Gold medals in the women’s 66-kilogram and 57-kilogram competitions.  They terrorised some opponents, e.g. Italian boxer Angela Carini who withdrew from her contest with Imane after just 46 seconds when her nose was broken, saying later that she had "feared for my life".

During the Olympics' it emerged that the International Boxing Association (IBA) had disqualified both boxers from a competition in 2023 as they had male XY genes.  The IBA refused to disclose what the boxers "had between their legs" as this was personal confidential information and they had been threatened with legal action if they provided the press with any more medical details than was already public.

However, the IOC granted both boxers permission to compete in women's boxing events.  IOC President Thomas Bach justified their inclusion in the Olympics by stating that DSD did not apply and "We have two boxers who were born as women, who have been raised as women, who have a passport as a woman and who have competed for many years as women."  The "born as women" statement could be interpreted as meaning being genetically XY with female sexual organs, but a 'clarification' quickly issued by the IOC made clear that this was not the case, and basically if you held a female passport you could compete in the Olympics as a woman.

Relevantly, Imane has explicitly denied that she suffers from DSD and so could be physically completely male.  However, she holds a female passport and the Algerian Olympic Committee and her father have emphasised that she was brought up as a girl and identifies as a woman - so she passes the IOC's criteria.

Whilst the two boxers have gained the headlines, observers - particularly on social media - have also questioned the "sex" of several other competitors at the games.  These can't be named here because of the lack of official confirmation and all the legal actions and countersuits being threatened or in progress.   

No one has emerged well from the transgender controversies at the Paris Olympics - the IOC, the IBA, most media outlets, transactivists, transphobics ... . The reality is that athletics such as Khelif and Lin are among the victims, they were told by the IOC that they could compete as women in the Olympics and so did in good faith.  The hail of personal abuse that they then received was brutal and often unfair; their gold medals will always be tarnished in the eyes of many; and record books are likely to list their wins with a caveat note. 

It will probably take a year or more before the dust settles and it becomes agreed where the male/female boundaries were pushed by Paris competitors to and perhaps beyond acceptable limits.  Maybe another attempt will then be made to arrive at widely acceptable and legal rules before the 2028 Summer Olympics in Los Angeles.