GMC states doctors:
Personal beliefs and medical practice
56. You must not abuse, discriminate against, bully, or harass anyone based on their personal characteristics, or for any other reason. By ‘personal characteristics’ we mean someone’s appearance, lifestyle, culture, their social or economic status, or any of the characteristics protected by legislation – age, disability, gender reassignment, race, marriage and civil partnership, pregnancy and maternity, religion or belief, sex and sexual orientation.
Conscientious objection
8 You may choose to opt out of providing a particular procedure because of your personal beliefs and values, as long as this does not result in direct or indirect discrimination against, or harassment of, individual patients or groups of patients. This means you must not refuse to treat a particular patient or group of patients because of your personal beliefs or views about them.5 And you must not refuse to treat the health consequences of lifestyle choices to which you object because of your beliefs.6