This World Rugby Transgender Guideline document has been developed to provide guidance and information in relation to the participation of transgender players in rugby. The terminology used when discussing issues involving transgender players can be controversial. A glossary is available here that contains more detailed explanations of frequently used terms. The glossary is provided to ensure that the Guideline is clear to everyone who reads it, but it is acknowledged that not all terms are used or agreed on by all people. For the purpose of this Guideline, we will use the terms "women's rugby" and "men's rugby" to refer to the existing participation categories in rugby union.

This Transgender Guideline aims to facilitate the participation of transgender players in rugby where it is possible to do so safely and fairly. Rugby is a sport that involves frequent physical confrontation and collisions and physiological attributes such as size, stature, strength and power are important contributors to player safety/welfare and performance. Given rugby's documented risk of injury and the prioritisation of player welfare, it is a sport that faces unique and specific challenges with respect to the participation of transgender players.

The Guideline was developed by a World Rugby working group following research into available scientific literature, detailed and extensive consultation where the working group heard from independent experts in the fields of performance, physiology, medicine, risk, law and socio-ethics, and subsequent research and consultation on matters arising from the meeting. the presentations delivered by each of those experts at the meeting are available on World Rugby's Player Welfare website.

Having carefully considered the currently available information, the working group determined World Rugby's current policy. A summary of the position for transgender women is set out below and full guidelines for transgender women are here, a summary of the position for transgender men is set out below and full guidelines for transgender men are here and the guidelines for non-binary people are set out here.

Summary for Transgender Women

Transgender women may not currently play women's rugby

Why? Because of the size, force- and power-producing advantages conferred by testosterone during puberty and adolescence, and the resultant player welfare risks this creates

Risk of Injury is too great

It has been proposed that the suppression of testosterone for a period of 12 months is sufficient to remove the biological differences that create performance differences summarised above.

Research contradicts this, consistently showing that total mass, muscle mass and/or strength are reduced by at most 5% to 10% when testosterone is suppressed to levels in the female range, for a period of 12 months. With the additional factor of training, either before or during the period of testosterone suppression, it is expected that baseline/pre levels for these variables will be higher, and that training will attenuate the decline in these variables with testosterone reduction. The consequence is that given the size of the biological differences prior to testosterone suppression, this comparatively small effect of testosterone reduction allows substantial and meaningful differences to remain. This has significant implications for the risk of injury in rugby.

Forces and inertia faced by a smaller and slower player during frequent collisions are significantly greater when in contact with a much larger, faster player. Research has found that the discrepancy in mass and speed is a significant determinant of various head injury risk factors, including neck forces, neck moments and linear and angular acceleration of the head. When two opponents in a tackle are significantly different with respects to mass or speed, these risk factors increase significantly. All these factors are 20% and 30% greater when typical male mass is modelled against typical female body mass in the tackle. Further, the ability to exert force (strength and power) is greater in biological males, and the ability to receive or tolerate that force is reduced in relatively weaker players. Collectively, this means a dynamic tackle situation would create a large increase in risk for players who lack these physiological attributes relative to their opponents. Similarly, scrum forces are significantly greater in men's rugby (twice as high for elite men vs elite women, and 40% higher for community level men compared to elite women). The implication of this finding is a significant increase in injury rates in contact situations, since the magnitude of forces and energy transfer in those contacts will increase substantially as a result of the collection of physical attributes that differ by biological sex.

World Rugby's number one stated priority is to make the game as safe as possible and so World Rugby cannot allow the risk to players to be increased to such an extent by allowing people who have the force and power advantages conferred by testosterone to play with and against those who do not.

Retention of Meaningful Performance Advantages

Given that the typical male vs female advantage in the above-described biological variables and hence performance outcomes ranges from 30% to 100%, a substantial and meaningful advantage is retained even after testosterone suppression. This has implications for performance, given the premium on contact and collisions, speed, force­ production and power in rugby.

A detailed explanation of the biological rationale, along with explanations of the effects of testosterone and its potential influence on safety and performance  factors can be read in the guidelines for transgender women here.

Summary for transgender men

Transgender men may play men's rugby having provided confirmation of physical ability. Transgender men may not play women's rugby after the process of sex reassignment has begun, if this reassignment includes supplementation with testosterone

Why? Transgender men need to provide confirmation of physical ability to ensure that they are not putting themselves at an unacceptable level of risk when playing against men.

A detailed explanation rationale can be read in the guidelines for transgender men here.

Commitment to ongoing evaluation and evidence-based guidelines

World Rugby is fully committed to evidence-based player welfare decisions. As such, the present guidelines have been developed by assessing all currently available scientific evidence pertaining to  biological and physiological differences  between biological males and females, and the effects of testosterone suppression on those differences. Related to these changes are known injury risks and risks factors, which have produced these guidelines.

The Guidelines remain subject to the presentation and publication of new evidence. World Rugby are thus committed to a formal review of the Guideline every three years and will remain current with respects to all available high-quality evidence, with a view to modifying, changing to improving upon this document in future. In support of this, World Rugby has also committed to including transgender research in its annual research priorities and inviting academic institutions from around the world to submit proposals that may be funded if deemed sufficiently high quality. In this way, these guidelines are open to change, as led by high-quality evidence.

Inclusion

World Rugby is committed to encouraging transgender people to be involved with rugby. World Rugby actively encourages transgender players to be involved with rugby whether in coaching, refereeing, administration or non-contact forms of the game and World Rugby will offer training courses to those who may find that the way that they are involved in rugby must change because of this Guideline. Further details are available within the individual guidelines.

World Rugby is currently funding research into the safe participation of all players in rugby. Details of the research currently underway, along with details of how to apply for research funding for those who may be interested in that, is available here.

Mixed-Gender contact rugby

World Rugby is currently exploring the possibility of an "open category" of rugby in which any player could play, regardless of gender. World Rugby has committed to exploring this option with its Unions, Associations, International Rugby Players, and trans-advocate groups including Gendered Intelligence and International Gay Rugby.

Mixed-Gender non-contact rugby

All players (including transgender players and players with DSD) can play mixed-gender touch or tag rugby.

Union Responsibilities

It is strongly recommended that each Union adopts its own regulations to determine the eligibility of transgender players to compete in events taking place under its own jurisdiction. Unions should take account of the information provided in this Guideline but may also take into account any relevant aspects of local law which apply within the Union's jurisdiction and with which the Union is legally obliged to comply. See here for further details.

Transgender Information

What does transgender mean?

The term 'Transgender' is used in this Guideline to refer to individuals whose gender identity (i.e. how they identify) is different from the sex identified at birth (whether they are pre- or post-puberty, and whether or not they have undergone any form of medical intervention).

Transgender man: a term used to describe someone who is identified as female at birth but identifies and lives as a man. This is sometimes shortened to trans man, or FTM, an abbreviation for female-to-male.

Transgender woman: A term used to describe someone who is identified as male at birth but identifies and lives as a woman. This is sometimes shortened to trans woman, or MTF, an abbreviation for male-to-female.

A glossary is available here that contains more detailed explanations of frequently used terms.

What about players with differences of sex development (DSD)? 

People with "Differences of Sex Development" (DSD) are not transgender (necessarily, although a person with DSD could of course identify as transgender). DSDs are a group of rare conditions involving chromosomes, hormones and reproductive organs which usually results in a person's sex development being atypical. Numerous DSD conditions exists, with different implications  for  sporting performance, and they should thus not  be considered as a single group.

A separate World Rugby guideline will be developed in 2023 for players with DSD. In the meantime, players should be dealt with on a 1 on 1 basis by their Union Chief Medical Officer, using the principles of Safety, Fairness and inclusion whilst taking into account the potential benefits of androgenisation in these cases.

Future research funding considerations

As described previously, the current evidence strongly suggests that the reduction of testosterone levels in transwomen is insufficient to remove biological advantages created during puberty and adolescence, which is the basis for the current policy that disallows transwomen from playing in women's rugby. This is however based on current evidence, and does not preclude the possibility that future evidence, specifically in an athletic, trained population, may emerge to contradict this position, and offer alternative policies.

To this end, World Rugby is committed to supporting such research as part of its global research prioritization. Currently, World Rugby invites research proposals from any eligible applicant, and then assesses the applications through a Scientific Committee comprised of internal and external independent researchers and experts. Those studies that are deemed to fall within the high-priority research areas, and to be of sufficient standard, are then funded by World Rugby.

As part of its commitment to an open, transparent engagement with the rugby-playing community, matters related to transgender physiology and performance will henceforth be included in the World Rugby high priority research areas. This means that any researchers who are exploring questions related to biological differences between males and females can apply to World Rugby for funding. This is not a guarantee that funding will be provided, as the studies are evaluated against a checklist according to best-practice principles, but the field of research will be prioritized, and so candidates may apply for funding that will advance understanding in this field and ensure that the policies that govern the sport are continuously challenged by best-available evidence.

See further details on World Rugby's research process and application for funding here.

Queries

• In the case of general queries regarding this Transgender Guideline, please contact: Head of Technical Services, World Rugby, World Rugby House, 8-10 Pembroke Street Lower, Dublin 2
• In the case of confidential queries regarding cases affected by this Transgender Guideline, please contact: Chief Medical Officer, World Rugby, World Rugby House, 8-10 Pembroke Street Lower, Dublin