Helloo, Your mother's problem is pain abdomen(stomach), the first step is to understand where the pain is coming from !That can be got from a history(assosciated symptoms ) and examination.
Since u have been to a doctor who has got the usg done, let me reassure u that it is not a very uncommon finding to see a bulky uterus
. It is usually assosciated with infection ----> use antibiotics for about 10 days, or excessive bleeding during cycles ----> get Hb done if less than 10 G % use Iron and vitamins
So, the need for Surgery ? It is a last option, when the bleeding is very heavy and there is a DROP in Hb to
Perhaps I would advise you to get another check done up to consider other causes of the pain as well.