Had endometrial ablation several years ago.periods became much lighter, but a few times a year it's heavy.how could this be if lining was frozen off.

Tissue left: There are several ways of a ablating the endometrial lining but there is no way of 100% eliminating all endometrial tissue. Most people are heavy with the reduction in bleeding. However they can experience recurrent bleeding. If it's still heavy see your Gyn for alternative options. I usually offer multiple options that are suitable to my patients preferences to control the bleeding. Best wishes