This issue touches on complex topics like biology and fairness in sports and the meaning of categories in athletics.

I'll break down the key facts for you and explain why this matters for the future of women's sports.

So two Olympic boxers, Ameen Khalif from Algeria and Lin Yuting from Taiwan are at the center of the storm.

Both have competed in women's boxing for years but recently their eligibility has been questioned.

The International Boxing Association says that tests show they don't meet criteria for women's competition however the International Olympic Committee is still allowing them to compete.

This has caused confusion and heated debate.

Some people have wrongly assumed that these athletes must be transgender but that is not the case.

Instead this controversy is about a complex topic called disorders of sex development or DSD.

To understand this issue we need to talk about biology.

In most people biological sex is straightforward. 2x chromosomes mean that you are female and xy chromosome means that you are male but nature isn't always that simple.

Some people have conditions called disorders of sex development or DSD.

In sports the most relevant DSDs affect individuals who are genetically male but appear female at birth.

The two important types are 5-alpha reductase deficiency 5ARD and partial androgen insensitivity syndrome PAIS.

People with these conditions have xy chromosomes.

They have internal testes instead of ovaries.

They produce testosterone in the normal male range however they often appear female at birth and are raised as girls but they do experience male-like changes during puberty.

Testosterone is crucial in this debate because it's incredibly powerful for athletic performance.

Testosterone affects muscle mass and strength, bone density and the oxygen carrying capacity of blood.

The difference in testosterone levels between typical males and females is huge.

Adult males have about 10 to 30 times more testosterone than adult females.

There's no natural overlap.

Even females with the highest testosterone levels will not have more testosterone than males with the lowest levels.

This is why sports are divided by sex.

Without this division very few women would be competitive in sports at elite levels.

The IOC's current approach is to use a passport test.

If an athlete's passport says they're female they can compete in women's events.

This might seem simple but it ignores the biological realities we've just discussed.

A passport doesn't tell us about an athlete's chromosomes, hormone levels or physical advantages and this creates problems for fairness and competition.

This actually isn't a new issue.

Women's sports have dealt with questions about intersex athletes for decades.

A famous example is Caster Semenya, a runner with 5 ARD who won Olympic gold medals in Rio and London.

Semenya identifies as female but has XY chromosomes and testosterone in the typical male range.

It's They are playing by the rules.

They've identified as female their whole lives but their biological advantages raise questions about competitive fairness.

The situation no doubt creates huge ethical challenges.

On the one side we have athletes who have always identified as women and who want to compete.

On the other side we have concerns about fairness for athletes who do not have disorders of sex development.

There's no easy answer that makes everyone happy.

Some experts suggest using chromosome testing as the first step.

This wouldn't automatically disqualify athletes with XY chromosomes but it would be an important first step in ensuring fairness.

Others propose creating new categories for athletes with disorders of sex development but this would pose its own challenges of course.

As we've seen the issue is complex.

It involves biology, ethics and the very nature of sports categories.

The current controversy shows that we need clearer science-based guidelines that prioritize fairness for female athletes.

The passport test is not fit for purpose.

As fans and supporters of sports however it's important to approach the topic with empathy for everyone involved but we do need to maintain meaningful competitive categories in the Olympics.

Thank you for watching.

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