This query is for my niece, who is around 20 years old. She has extreme low Hemoglobin, ranging between 6-7 . It is same since long time, atleast last 6-8 months. So she feels fatigue and weakness most of time. Recently have low grade fewer too since last few days. Regarding this I have following questions : 1. What can be cause of this extreme low Hemoglobin, does it somehow hereditary as other family members also have more or less same health condition. 2. Does these symptoms are indicating any serious issues ? ??? 3. As per my knowledge, iron deficiency can be overcome within 2-3 months, if treated properly. What kind of doctor we should visit, which specialist ? Please suggest. Thanks.