What Causes Excessive Vaginal Bleeding Along With Abdominal Pain?

Hai hello....my mom age is 45...she is 45 years old....she is suffering from over bleeding with stomatch pain since last 5 months...in first month end itself,we consulted with dictor and came to know that my mom haemoglobin s very low...so we had some medicines and given three units of blood and scanned the uterus and done biopsy also..atlast result is positive in everything.....there is no problem in my mom uterus..... next month it got reduced....but again next month itself again the same bleeding with no stomach ache...so we went to consult doctor again doctor prescribed restrogone 5 mg tablet for 20 dats and ask us to come in next peeiod time.....once the tablet over,again same problem started with heavy stomach ache and bleeding was also very high....so we went to new doctor ,prescribed trapic mf .....when she have that, for sometime,there s less bleeding and stomach ache....but after sometime thy again started to over bleeding...so kindly request you ro send the solution...whether its safe to remove the uterus or not?