What happens at the first visit
A long list, mostly blood tests, mostly worth having.
Expect a long appointment. A detailed medical and family history, blood pressure, weight and height, and a panel of blood tests: blood group and antibody screen, full blood count, immunity to rubella, hepatitis B, syphilis, HIV, and usually urine testing. Chlamydia and gonorrhea screening is offered depending on age and risk.
Most of these are straightforward and finding something abnormal is genuinely useful. HIV testing in pregnancy is the clearest example: treatment reduces transmission to the baby to a very low level.
You may also be asked about your mental health, about safety at home, and about substance use. Those questions are asked of everyone, and how the answers are used is not always equal. See the topic on discretionary care.