Thyroxine dosage advice in pregnancy

[Bobbob]

Hi! I am 15 weeks pregnant with twins. I don't have a thyroid as it was taken out over 20 years ago due to a malignant tumour. I had a blood test last week and my reading was TSH=0.07 and FT4=18.7. My GP says I don't need to increase my thyroxine dosage and unfortunately I am not going to be seeing an endocrinologist anytime soon to get this confirmed by an expert. Please could someone confirm that my blood results are fine and no changes are actually necessary to my dosage? I thought I would have needed to increase my dose by now! I am on 175 mcg of levothyroxine per day. Thanks in advance!

[Clutter]

Bobob, congratulations on having twins, you must be very excited

Your results are absolutely fine and you are optimally dosed. NICE recommends TSH of pregnant women should be in the low normal range 0.4-2.0 during the first trimester, up to 2.5 during the 2nd and up to 3.0 during the 3rd, with FT4 in the upper range. Don't worry that TSH is a bit lower, it's enabling good FT4 which is more important than TSH. Your babies have developed their own thyroid glands and are no longer dependant on you for thyroid hormone, so you should reduce dose a little if you start feeling overmedicated.