Q: My 34 years old wife has recently been diagnosed with hypothyroidism. Her levels are - T3 - 1.56 (normal), T4 - 7.18 (normal) and TSH - 15.33 (elevated). This was detected as my wife missed her menstrual cycle and we approached a gynaecologist to test for pregnancy, which came negative. Subsequently, we were referred to an endocrinologist who started her on 50 mcg of thyroxine for 10 days followed by 100 mcg for ten days and then 250 mcg for 40 days. I have certain specific queries about hypothyroidism-

1. Considering my wife's age, will it be difficult for her to conceive with thyroxine treatment?
2. I was told that children conceived with high TSH levels, might be born with low IQ. Is it true?
3. If the child will be affected by my wife's hypothyroidism, what is a safe period we should abstain from planning a baby?
4. What are the side effects of thyroxine tablet?
5. Will my wife continue to gain weight during the course of thyroxine treatment?

A:Your wife should not need more than 75-100 ugm of thyroxine; 250 ugm is a very high dose. I would suggest she take 50 ugm for 15 days followed by 75 ugm daily for next 30 days and then get the TSH repeated. If it is normal, then continue 75 ugm; if it is low then reduce to 50 ugm and if still high, then increase to 100 ugm per day. Answers to your specific queries are as follows:

1. It will not be difficult to conceive due to disease or medication.
2. It is recommended to plan a pregnancy once TSH is in the normal range otherwise there may be complications in the baby.
3. The only requirement is that the TSH should be in the normal range.
4. In normal doses (TSH in normal range), there are no side effects but if given in high dose (as denoted by low TSH) then it can have impact on heart and bone leading to irregular heartbeats and osteoporosis.
5. If her lifestyle is sedentary and she overeats then yes, otherwise there will not be any weight gain.