Which component of vital signs is not typically measured during a routine check-up?

During a routine check-up, the measurement of vital signs typically focuses on parameters that provide immediate insight into a patient's physiological status. These usually include body temperature, heart rate, respiration rate, and blood pressure. While weight and height may also be recorded to assess growth and body mass index (BMI), blood glucose levels are not standard vital signs.

Blood glucose measurement is a specific test often conducted separately to evaluate a patient's metabolic health, typically in the context of diabetes management. It is not routinely checked as part of vital signs since vital signs aim to reflect immediate physiologic function rather than metabolic states.

Thus, blood glucose stands out as the component that is not typically included in the standard measures of vital signs during a routine check-up, making it the correct answer in this context.