Hypothyroidism & MC/TTC

Paige
I had a miscarriage at almost 8 weeks in March. Since then, I've continued to gain weight, no matter what I do (eating clean, tracking calories, working out). I'm up almost 20 lbs from my pre-preggo weight. I know my body, and I know this isn't normal. 
Has anyone else developed hypothyroidism during pregnancy, or before? Apparently it's a common occurrence and can cause a MC. I'm going to get blood tests done on Wednesday and I'm hoping for some answers. 
I just wanted to hear some other stories of ladies who have had something like this occur.