World Ruby have announced they will be conducting a "comprehensive review" of their policy on transgender players.

The review comes in light of recent research suggesting that reducing testosterone levels does not proportionately lower strength and power and could thus be a danger and an advantage in contact sports.

World Rugby chairman Sir Bill Beaumont said: "World Rugby's vision is 'a sport for all, true to its values."

He added: "There is growing recognition of the importance of autonomy of gender identity in society and all sports are currently evaluating their policies to ensure that they are fit-for-purpose in the modern sporting and societal landscape.

"Rugby is no different and this forum makes it possible to explore the best available evidence and hear the relevant expert opinions."

World Rugby currently follows the policy issued by the International Olympic Committee (IOC) which states that transgender athletes must suppress their testosterone levels and keep them below a threshold of 10nmol/L for at least 12 months prior to competition.

This level was more recently reduced to 5nmol/L and must still be maintained for 12 consecutive months.

Testosterone is considered to be the male hormone and is responsible for increasing muscle mass.

Athletes transitioning from female to male are permitted to participate without any restrictions, but new guidelines are being developed.

The rules are there in order to create a safe environment for players and ensure a level playing field.

"It is important for contact sports, such as rugby, to find an appropriate position for player welfare and risk," a statement from World Rugby said.