What type of health hazard does drinking period blood by mistake impose?

There are no health hazards associated with accidentally consuming one's own period blood. Menstrual blood is a natural bodily fluid and is not harmful if ingested. However, it may be unpleasant or distasteful to some people. If you are concerned about accidentally consuming your period blood, you can use a menstrual cup or other menstrual product that collects the blood rather than allowing it to flow out of the vagina.