Q: I am 4 months pregnant. I recently did a blood test and found that I have a high TSH of 5.02. I was put on Thyronorm 25 mcg. What is the affect of this medicine on the growing baby in my womb? Can this be completely cured with drugs? How long does the treatment last?

A:At 5.02 mu/L, your TSH level is marginally above normal range (0.5 to 4.7mu/L). In order to check possible laboratory error, ideally the test should be repeated to reconfirm the level. If it is still high, unbound (free) T-4 level can be determined to come to the conclusion that you are suffering from very mild hypothyroidism. If so, it is quite appropriate to take thyroxine 25 mcg daily sold under various trade names such as Thyronorm, Roxin etc. TSH and T-4 (free) level should be measured again at six months gestation to ensure that your thyroid activity is normal. If not, then thyroxine dose may need to be increased. Thyroxine is given to women suffering from hypothyroidism to prevent foetal neural tube defect.