Lady MacBeth washed her hands after she’d bloodied them. Diabetics should wash before.
Having clean hands is always a smart idea and it’s a particularly good idea to wash up before you check your blood sugar. This doesn’t have to do with bacteria or risk of infection since it’s very rare to get an infection at a lancing site, but rather with getting a more accurate blood glucose reading. We almost all come in contact with sugar during the day, especially those of us who are serving cookies and milk to our kids, and having even a tiny bit of sugar on a fingertip could lead to a false reading. Other substances like hand cream can also interfere. So take a minute to wash your hands before you prick (as long as your not having a major hypoglycemic attack – in which case, understandably, you’re probably thinking about food, not hygiene).
*Be sure to dry your hands well since water could dilute your blood sample and lead to a false low.