On April 16, 2025, the United Kingdom (UK) Supreme Court ruled that the legal definition of “woman” refers to biological females; the judgment also stated that biological sex is “binary” [1]. Less than ten days later, on April 25, 2025, the BMJ published an editorial titled “Sex and gender should not be conflated in medical data” [2]. In the editorial, authors Margaret McCartney and Susan Bewley critique the interchangeable use of sex and gender in medical data collection — a practice prevalent in the recordkeeping of the National Health Service, UK — and argue that such a conflation runs the risk of medical practitioners making erroneous decisions and diagnoses [2]. While recognising that “A few people are found to have one of a small number of clinically recognized variations in sex development”, the authors too suggest that biological sex is a binary (“male or female”) [2].