If you have heavy menstrual cycles most likely you are deficient in iron as chronic and continuous blood loss causes an deficiency. Usually vitamin B12 deficiency will occur when there is a chemical in your stomach called intrinsic factor missing. I doubt you have vitamin B12 deficiency. If you have iron deficiency anemia your choices for treatment are several. You may take a diet high in iron however usually if your iron levels are low you'll need more supplementation. You may take oral iron medications such as ferrous sulfate which will slowly raise your iron level. These preparations may irritate your stomach and making your stool black. you may also receive intravenous iron preparation called iron dextran which will bring your iron levels up more quickly however there are side effects of headaches and flushing. The quickest way to bring your blood levels up if they are life-threatening would be blood transfusion. Although I understand you're trepidation blood transfusions currently are very safe as they are tested for viral contaminants such as HIV and hepatitis C. You must choose one of the foregoing suggestions as having an anemia if it is severe can be dangerous as the Oxygen flow to your heart and brain can be compromised.

*****Click ***** "ACCEPT" (GREEN) ***** or I do not get credit for my answer and Just Answer holds your deposit. Take a moment to leave a ***** POSITIVE ***** feedback which does not cost you anything. This response is for your information only and does not substitute for a visit to your doctor.