Hi, am 45 and 7.5 wks pregnant. Was diagnosed as borderline thyroid in 2012/13 and also had v low iron (5) and low B12. Dr gave me supplements and 50mg levo. Took the levo for a couple of weeks on a couple of occasions and had to stop as heart was too racy. TSH seemed to normalise itself a little so I stopped taking levo and ferrous fumarate (was on 3 a day) and 2 b12 per day. Did have a miscarriage in 2011 but wasn't aware of any thyroid issue then (had not been tested either). Now found out am pregnant again. At blood test on 8 Dec (5 wks preg) TSH was 4.35. Iron was 12 and B12 around 300 (on pregnacare max). On 23 Dec TSH was 5.08. On 10 Dec I started on 50mg levo and dropped to 25mg after a week cos heart palpitations. Took 25mg for few days then after the result on 23 Dec, the private doc trying to help me prevent miscarriage again told me to up the levo to 75mg. Yest I went to A&E as had some bleeding (I actually think it could be rectal bleeding as constipated). They took my pulse and said it's too high at 89, range is 60-90. He told me to drop levo as 75 is too high. Am so confused. I want to support this pregnancy yet fear that I am unable to take the levo. What should I do? Drop back to 25mg daily? The private fertility doc has also put me on prednisolone, clexane, progesterone and suggested a baby aspirin daily. Have never taken so many drugs! Any advice appreciated. Wondering if I try and up my iron level by taking a ferrous fumarate daily (plus the pregnancare max where the iron level is low anyway) it might start to resolve itself again, but I understand pregnancy can take a real toll on tsh.