New rules in Australia in respect of transgender recognition and the acknowledgment – the first ever by any government – that intersex individuals can now opt for "X" on their passports may look like minor bureaucratic tidying. Longer term, however, the consequences for gender identity and identification are likely to be worldwide and seismic.

What has changed?

In future, a letter from a medical practitioner certifying that a person has had, or is receiving, appropriate clinical treatment for gender transition will suffice for them to obtain a passport in that gender: "M" or "F". Likewise, those who are certified as intersex will be able to obtain a passport marked "X". According to the Australian passport office, this will denote "indeterminate/unspecified/intersex".

Are they confused?

Possibly. Statements from the Australian government reference "sex" and "gender" almost interchangeably, although on the Australian passport the box in question is marked "sex". That elision of difference between the two is at odds with a great deal of current social scientific and feminist thinking, which regards gender as social construct and sex as biological. Conflating trans and intersex issues as they have done is therefore not necessarily helpful. It is also not entirely clear whether the intent is to create a third option, which is denied, or simply to identify a "none of the above" category.

However, the suggestion that "X" is reserved for intersex individuals does support the idea that a third option is being created, as opposed to a simple alternative for those who choose not to disclose their gender.

How does this compare to the UK and elsewhere?

According to the EHRC, the UK passport service already allows gender to be changed on the basis of a letter from a medical practitioner: it does not require gender reassignment surgery to have taken place. The US shifted to a similar position last year. In France, by contrast, a series of recent court cases suggests that surgery is needed. Australia is the first government anywhere in the world to provide recognition to the intersex minority.

Could the UK go the same way?

It depends on what change Australia has put in place. There is no international legal requirement that passports include gender: and any country that complies with the International Civil Aviation Organisation's specifications for machine-readable passports can choose to introduce an "X" gender/sex.

In the UK, passports are issued under royal prerogative: so a change could be implemented next week, if the government so desired. According to a report by trans support group Gires, a similar reform in the UK could eventually affect up to 90,000 individuals. The implications for intersex are far wider: best estimates suggest up to 4% of the UK population could carry some form of intersex variation – often without being aware of it.

However, in a debate on abolishing ID cards last year, Lib Dem Julian Huppert raised the issue of why many official documents required gender on them at all. This is a fair question: for trans individuals, having a passport with their identified gender on it may be a matter of safety when travelling to less tolerant countries. For everyone else, the question now on the table is why does my passport need gender at all?