Removing the ovaries with a hysterectomy is common. In fact, of the 600,000 hysterectomies performed every year, half of them include the removal of the ovaries - the reason behind it being cited as cancer prevention (of the ovaries).
The fact is that our ovaries are important to our health - even when we are beyond child-bearing age. They have been linked to heart attack prevention, lessening risks of stroke and even dementia.