Expert answer:
Most blood tests can be done while menstruating, but some tests may have different results, so it is important to ask the doctor if there is going to be a problem in doing the blood test that he requested when menstruating.
The blood used for the laboratory tests is the blood that circulates through the blood vessels of the body, having no direct relation with the blood goes out through the vagina, which is actually the inner layer of the uterus that bleeds when there is no pregnancy, that is, the menstruation, which happens every month.
The doctor responsible for the examination request or the person in charge of the laboratory where the blood will be taken may specifically advise on the preparation for the examination requested.
