Autumn 2025 was a landmark year for medical research in the UK. The government's National Institute for Health and Care Research has adopted a sex and gender policy for funded research. The Wellcome Foundation, a major charity, has adopted the same policy. Several medical research charities have updated their guidelines for applicants for funding. These include Breakthrough T1D, the British Heart Foundation, the Cystic Fibrosis Trust and Fight for Sight. These changes ensure that researchers design robust plans to account for gender in research. The policies represent a leap change for medical research.