Hi and thanks for the query,
It is true that thyroid hormone has an important role to play as far as skeletal growth (bones) is concerned.

Considering the fact that your daughter was diagnosed with hypothroidism at a pretty young age, and I assume has been on proper treatment, effects of thyroid insufficiency should not actually be a cal for concern.

It is important to know if she experiences any signs of hypothyroidism (Intellectual quotient, cold intolerance, constipation, obesity etc)? If she does not experience any of these, or has not been experiencing any of these, then her thyroid replacement therapy should certainly be within normal limits. In case she presents with these symptoms, it might be worthwhile consulting, controlling and concerting with her endocrinologist with respect to her treatment..

Considering appropriate thyroid replacement therapy, she should grow normally as others. But considering that she had already experienced some deficiency consequences in the uterus before starting therapy, fortunately early enough, it is not unusual that she could have a shorter height/stature with respect to others. She is still 12, she was put on thyroid therapy quiet early in life, she still has a very high potential of growing very well, and the difference in height with her peers should not really be that pronounced assuming the control has been perfect. Controlling her growth hormone blood levels also could be of help, since thyroid and growth hormone are quiet linked in their respective metabolic pathways and actions.

For now, be calm, get the opinion of the endocrinologist, screen for growth hormone. Her hormone supplementation was early enough and in case there are no signs of hypothyroidism that she experiences, her potential of growing well with respect to height is still not compromised.

Thanks and hope this helps as I wish you the best of health.

Best regards,

Luchuo, MD.

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