ultrasound

i am 56 and for the past year have been getting my period every three months. The lining of my uterus has been 14, 11, 12. I've had a procedure called "pilpul" done and the lining went down but after three months it's back to 11 I was told to take another ultrasound but will this keep repeating and should i have another "pilpul" done? Thank you.