1/ There is nothing so divisive in the world of protecting women's sport as the topic of CAIS, complete androgen insensitivity syndrome.
I have seen opinions on both ends of the spectrum on this, and would like to clarify my position.
This will be quite a long post, and probably the only time I will ever talk directly about CAIS.
2/ Complete androgen insensitivity syndrome is a disorder of sexual development (DSD) in which, like the name suggests, the body is completely insensitive to androgens (the "male hormones"), which are necessary for the development of male genitals and secondary sex characteristics.
To be perfectly clear, the individuals affected by CAIS are male. It is considered a male disorder.
These individuals are born with XY chromosomes, testes, and lack all female reproductive organs including the ovaries, uterus, and fallopian tubes except in extremely rare cases.
3/ I have seen the claim that these individuals have a "female phenotype." I believe this is inaccurate.
A female phenotype does not include functioning testes and a lack of female sex organs. Primary sex organs determine our sex.
Female human beings are not males with disorders. We are not feminine looking individuals. We are not classified as individuals insensitive to androgens. We are our own unique sex class with a body organized around the production of the large gamete.
If a medication existed that could treat the condition, these individuals would immediately masculinize like all other males.
I also believe and have stated over and over that women are "adult human females." As such, males with CAIS are NOT women by the definition we have been fighting so hard to protect.
"Woman" is not a "social" or "legal" identity. It is a biological classification.
4/ That being said, because individuals with CAIS are not affected by androgens, they experience none of the development expected in typical males.
The testosterone produced by their testes is instead aromatized into estrogen which then feminizes the body just as it would in a healthy female individual.
Because androgens are converted into estrogen, individuals with CAIS develop secondary sex characteristics at puberty typical of female individuals (breasts, softer skin, wider hips) and an external vulva. They may also have a vagina (of varying depth) though it might be more accurate to describe it as a blind pocket.
They also do not experience the affect of androgens on the body in the mini puberty during infancy which all other males do.
This also affects development and possibly sexuality, as individuals with CAIS are more often observed as being attracted to males.
5/ What all of this means is that individuals with CAIS, at least externally, are almost physically identical in appearance to female human beings. It would seem they are similar in behavior as well.
It is their natural body, not something they have chosen to do to themselves, and with insensitivity to androgens, is not something they can even attempt to change with the use of HRT.
It is the only body they have to go through life with and is not something they should be forced to change (removal of testes) or attempt to masculinize or feminize.
Many of these individuals do not find out they are male until puberty, when they might go in for an exam due to lack of menstruation.
6/ The condition was not even discovered until 1953, so prior to that, these individuals lived their entire lives believing themselves to simply be infertile women, and the rest of society believed them to be and treated them as if they were female as well.
This means that for the entirety of human history, the struggle of women and girls has belonged to individuals with CAIS as well.
Males with CAIS have suffered every historical injustice that female human beings have.
They were sold as brides, killed at birth for want of a son, made to bind their feet, forced into corsets, treated as property by their husbands, denied education, denied the right to own property, denied the right to vote, victimized through sex trafficking, objectified by men and boys, and treated as lesser human beings.
They were denied many opportunities in sport in the U.S., the same as all female athletes, prior to Title IX.
7/ Even today, individuals with CAIS are treated no differently than female individuals as we move through society.
Members of the Taliban are not going around groups of women with ultrasounds and telling the individuals they find with testes they can take off their burqa.
The fight for women's rights has included them every step of the way.
As such, I find it incredibly insensitive to refer to these individuals as if they are no different than the perfectly healthy, fully developed men who have acted as their oppressors throughout history as well.
This is a group of males so unique from the rest of the male sex that they warrant special accommodations in society, which I believe includes access to women's spaces and services.
We already do make exceptions in these spaces to very young male children, and although we often call them "women's" bathrooms, it is understood they are for girls as well.
The fact that TRAs exploit this (both young boys and CAIS) to excuse the presence of TIMs in the bathroom should not force us to remove these protections from the individuals who actually need it.
8/ It should be understood that males with CAIS have nothing to do with the men and boys with healthy development who take puberty blockers, slice themselves up, inject themselves with drugs, put on dresses and wigs and makeup, and force their way into women's spaces all while wearing us as a costume.
Those men are cosplaying the bodies of individuals with CAIS as well, sometimes even claiming to have the condition themselves.
This is the only group of males I do not have a problem with people referring to as "women" and "girls," but I do believe it should be clarified in law that they are "males with CAIS."
The law needs to be accurate.
Any laws that are made regarding women's spaces should specifically clarify that they refer to female individuals and male individuals with CAIS if these individuals are to be included.
9/ The only area that I have an issue with is women's sport.
At the 1996 Olympics, there were 8 athletes in the women's category discovered to have been SRY positive. One report clarifies that one had 5-ARD, four had PAIS, and three had CAIS. (All were still allowed to compete).
This means that there were similar numbers of CAIS and PAIS athletes and the incidence of CAIS at these Olympic games was 3/3,387 or about 1/1,000.
The incidence of CAIS in the general population of males is anywhere from 1/20,000 to 1/99,000. This is quite a large overrepresentation, and there were more in that Olympic games than there were males with 5-ARD.
At the 1992 Olympics, 15 males were discovered in the women's category, but no breakdown of conditions is available.
10/ Males with CAIS benefit from any male advantage that does not come from testosterone.
I'm not sure of everything this would include, but they are taller on average, have longer limbs, and do not experience menstruation, not because of personal differences in genetics or a female disorder, but due to the fact that they are male. These are all categorical advantages.
WA believes it is fair for these individuals to compete in the women's category despite not being female, and like with all other males ("trans" and androgen sensitive DSDs) they seem to have done no studies beforehand to support this.
The habit of WA and the IOC, all athletic organizations, really, to default to allowing males into the women's category and forcing women to prove unfairness after the fact is exhausting.
11/ Studies should be done on the advantages of being male in regards to CAIS males BEFORE they are allowed to compete. If there truly is no advantage to be found, we can then make decisions on their inclusion.
Women's elite athletics are not a "right" that everyone should be included in. They are not for males with disorders or for males we feel sorry for who have been born with unfortunate circumstances.
You are only included if you qualify in the correct category. Most of the population is excluded from these sports.
We could make a para-athletic category for individuals with CAIS so that they can still participate in elite sport.
12/ When I say "elite" I'm referring to collegiate level and above.
Realistically, at the high school level, it would be difficult to ensure this as some individuals might not even know they have CAIS themselves until late in their high school careers.
This does not mean they do not have an advantage. I know of two in high school who have won a combined 13 state championship track and field gold medals.
At the amateur level, we need to concede that it is not realistic to expect sex testing for weekend runs and local competitions.
With "trans"-id males, there is always a history that can be traced (and they are often obvious). With other males with DSDs, masculine appearances raise suspicion. With males with CAIS, there is neither.
13/ All of this being said, the exclusion of the 1 in 99,000 males who have CAIS (and probably even less in athletics) is not my fight right now.
For reasons I've just stated above, unless an individual comes forward declaring they have CAIS or WA shares the info they have gathered, there will never be any way for me to collect data on these athletes, and there will be no visible clues to even suggest their presence in competition.
My concern is with the fully developed healthy males and the androgen sensitive males with DSDs who are not only stealing medals and opportunities from women and girls, but doing so while insulting us, humiliating us, and invading our privacy.
14/ My goal is to give women fair competition in sport. It is not to insult or degrade individuals who have disorders that they did not choose, have no control over, and cannot change.
You are free to disagree with my positions on either end of the spectrum and share your perspective in the comments, but I am not really here for debate as this does not affect my work either way.
And please remember that these are human beings who also deserve to be treated with dignity and respect.
Please feel free to correct any inaccuracies regarding this condition that you have noticed above. I am not a biologist or expert in this matter.
Article (from the year 2000) on the 1996 Olympics: archive.ph/fkq9A
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1. Man is allowed to join a women's volleyball team, the Jaguars, for a tournament in Mexico.
2. The Jaguars are crowned champions of the tournament.
I never would have seen that coming, especially considering the fact that this was an open tournament where this grown man ended up playing teams of young teen girls.
🧵Males with DSDs aren't the only males in the African continent competing in women's sports. Let me introduce you to Hillary Kiprotich aka "Shieys Chepkosgei"
In 2019, Kiprotich/Chekosgei was arrested for impersonating a female nurse at Moi Teaching and Referral Hospital in Kenya under the name "Pamela Mulupi"
"Investigating officer Victor Omondi told the court that Chepkosgei was dressed in the nurse's uniform complete with a badge and was working at the Emergency Section when other nurses grew suspicious."
"The nurses alerted the police after they failed to find a 'Pamela Mulupi' on the interns register."
Kiprotich/Chepkosgei was sent to a women's prison, where officers discovered that the individual who had claimed to be a woman was actually a man named Hillary Kiprotich.
It also came to light that he had been participating in international marathon races in the women's category. Kiprotich admitted to both in court: "I was identified as male, but when I became an athlete, I registered myself as female."
🧵Because of the EO and Title IX (federal law), there shouldn't be or ever have been a single male athlete participating in girls' scholastic sports in the United States, but we all know that's not going to happen anytime soon.
Here's a recap of the boys who participated during the 2024-2025 season by sport as we move into the 2025-2026 season.
I've done this thread before, but there are quite a few notable names to add.
Note: athletes may appear twice due to participating in multiple sports
Volleyball:
Male athlete Henry Hanlon leads the San Francisco Waldorf team to a Bay Counties Conference championship, a CIF Div 6 North Coast Section Championship (a repeat of his 2022 title), and a second-place finish in the regional championship.
Hanlon also caused the Stone Ridge Christian team to forfeit a playoff game, ending their season.
A female player on his own team is benched all year due to Hanlon's participation.
Male athlete Aaron "Valerie" Silverman sparks controversy at Clarkstown North High School in New York when he stole a spot on varsity from a female player.
Female players are allegedly threatened with expulsion from the team if they speak out.
Silverman is given an All-League award. A female athlete is benched due to Silverman's participation.
"When Boys Run in Girls’ Races: A Data-Driven Look at Fairness"
Staggering analysis comparing the performance of high school male athletes in the boys' division versus the performances of those same athletes in the girls'.
"Veronica Garcia’s 400-meter time of 55.70 won a girls’ state title; the same time would have ranked him 993rd in the state compared to his male peers."
There are few surprises here, but shocking all the same for the fact that this has been allowed to happen...
(Link below)
"In the boys’ division, results followed a broad, expected spread, with most between the 20th and 70th percentiles and only 2 percent reaching the 95th percentile and higher—typical of a random cohort."
"In stark contrast, when competing in the girls’ division, performances clustered at the top, with half (53%) in the 95th percentile and above."
"when both groups [top and low-performing boys] entered the girls’ division, nearly all top-performing boys, and a majority of the lower-performing boys, placed in the 90th percentile or higher."
"The median placement in the girls’ division was first place."
🧵The case over male athlete Stratton "Becky" Pepper-Jackson is soon to be heard in the Supreme Court, so let's go over the facts. foxnews.com/sports/supreme…
Please let me know if I've gotten anything wrong. I'm not a legal expert, so some of this may be off. But here's the gist:
Stratton "Becky" Pepper-Jackson is a boy who demanded he be allowed to participate on "girls'" sports teams when he was in 6th grade despite West Virginia law providing female-only sports.
In 2021, he filed a lawsuit, claiming discrimination, and filed a motion for preliminary injunction, meaning he requested that the West Virginia law he was challenging not be applied to him while the case was ongoing.
This was granted and he was given special permission to violate state law and participate on the girls' team (based on the chance that the law could be unconstitutional and in violation of Title IX.)
In January of 2023, a district court determination that having girls' only sports teams does not, in fact, violate Title IX as Pepper-Jackson's team argued.
Pepper-Jackson's team appealed and it was again determined that Pepper-Jackson was still allowed to violate state law and participate on the girls' team while the case was ongoing.
In a report, ESPN stressed that Pepper-Jackson "finishes near the back of the pack" in cross country and track and field, ignoring the fact that Pepper-Jackson was born with a heart condition.
🚨In the spring of 2025, Minnesota AG Keith Ellison dismissed fairness for female athletes and justified the abuse of girls in Minnesota by claiming ignorance on the topic and citing "10, 9, 11 year-olds" who "don't care about winning."
Meanwhile, in his own state, not only was a male athlete dominating girls' softball, but it turns out another boy was stealing state championship medals in track and field.
Meet Elijah "Ara" Warren.
As a recent 2025 graduate, Warren participated on the "girls'" track and field team at Moorhead High School in Minnesota all four years.
During those four years, he participated in (and won) events including shot put, discus, hurdles, pole vault, and every sprint distance.
In 2023, as a sophomore, Warren finished 3rd at the MSHSL State Track & Field Championships.
At 2024 state championships, he placed 4th in the triple jump, only running the hurdles once all year.
Warren switched from the hurdles to throws his senior year for an unknown reason (it looks like there might have been a bit of weight gain), but still proceeded to qualify for the 2025 MSHSL State Championships in both the shotput and triple jump, placing 9th in the triple.