In my opinion,titration of your dose of levothyroxine was not proper.Were you tested for T3 & T4 levels also. If these were normal, then even with increased TSH, the increase in dose should have been mild say upto 75 microgram.I am still of the opinion that this dose should be 75 microgram even now & it should be adjusted every fortnight according to readings of T3,T4 &TSH levels till reading is stabilised. After this the time interval between testing can be gradually increased.
Definitely,disturbed level of thyroid hormone can increase chances of miscarriage. However,your sonography report seems normal.
Still, you are advised to take treatment under guidance of your doctor,particularly in reference to your thyroid levels to minimise the chances of miscarriage etc.