A young lady of 25 years of age, with a child of two months in her lap came for consultation for, a swelling at her neck, butterfly shaped, firm on palpation, she gave history of normal delivery two months before. She told that repeatedly TSH testing was done during pregnancy, it was normal in first and second trimester but was raised in third trimester but Gynae doctor did advice any treatment. Now she has developed this butter fly shaped swelling and reports are T4 1.15  low ,T3 97.9 and S .TSH 79.9 , and S.TPO antibodies 288.80.

I prescribed her stat away 100 mcg levothyroxine , calcium and vitD. What is the diagnosis for this disease? What will happen to this swelling after treatment, reduced to  one or two small goitres ?