If a person self-IDs as something that does not match their biological sex, and their biological sex is no longer recorded in their medical records, there are significant health and medical care implications and risks, including:
Reproductive health issues being missed or under diagnosed.
Pregnancies being missed and a lack of proper antenatal care.
Risks relating to medications and treatments including blood transfusions.
Blood donation. For example, females have a smaller blood volume than males of the same height and weight, so the amount of blood that can be safely collected is smaller.
Clinical interpretation of blood tests such as the haemoglobin test.
Platelets cannot be collected from female donors due to the increased risk of a rare but dangerous reaction called transfusion-related acute lung injury (TRALI) that is associated with antibodies in plasma.
Most medication dosages and some side effects risk profiles.
Calculation of dosages, toxicity, risk profile, and efficacy of the medication/treatment.
Most medical care is in fact significantly shaped by sex differences and needs to take sex into account for reasons of safety and efficacy.
The fact that some birth certificates can be changed means that none can be trusted as records of (biological) sex. There is no way of telling whether the sex marked ‘female’ on a birth certificate is the sex of someone born female, or whether it refers to someone born male—unless there is some marker that indicates the change. Policy makers should care about the consequences of changing sex on birth certificates for women as it will have an impact on medical research and the impending degradation of demographic statistics and historical research.
Another medical care issue with self-ID, is what has happened in the NHS in the UK, where Trans identifying male medical staff do not need to disclose their biological sex, and women who have requested women only medical staff and treatment teams are not allowed to refuse care from a Trans identifying male clinician or nurse, because ‘trans women are women’.