I have mild hypothyroidism. Could this have stunted my growth?

Last updated on August 22, 2020

Question:

Hi!

I am 16 years old. I would just like to ask you a question about a problem with my thyroid. When I was 15 and a half, I had to beg my parents to take me to see my family doctor because I lost the ability to sleep, and before that, I was really tired all the time. When I went in, he examined me and saw how large my thyroid was and thought that I had hyperthyroidism. The test results came back and I turned out to have hypothyroidism, but not that bad of a case of it. I then went back to the doctors a week later to get my blood drawn again, but this time everything was normal. I would then go in about every 2 or 5 weeks and get my blood drawn and always my levels would be fine. But the weird thing is that my thyroid is still pretty enlarged. About a week ago I started not to be able to sleep again, for about two days, then I went back to normal sleeping. So I think that it is flaring up again. The doctor prescribed me Synthroid, but I don’t feel any different on it. I don’t really show symptoms of being hypothyroid or anything like that and there does not seem to be anything the doctor can do.

I would just like to know if this could have caused my puberty to end early or for my growth to be permanently stunted. I have reason to believe this because all my life I was the average height for my age, and now I am 16 and 5’7. which is about 2 inches shorter than average for my age. Also, I think I entered stage 4 of puberty when I was like 15, or maybe even 14.5 and don’t think that I am done with it because I still only have peach fuzz on my chin, and really light sideburns that you can’t even see because they are not pigmented. Since then I haven’t really changed that much. If my thyroid gets under control will I rebound back and grow and continue on in puberty at a normal rate? Or has my thyroid not even really stunted my growth at all and I am maturing fine?

Thank you and I am sorry my question is so long.

Answer:

Let’s start with an overly simplistic description of the thyroid. Your thyroid’s prime function is to regulate your body’s metabolism. When it is overworking (hyper) it revs up your body too much, much like drinking way too much caffeine. You can’t sleep, you get jittery, your body temperature rises, and you start burning calories like they were going out of style. When it is under-working (hypo) it doesn’t keep the various functions going fast enough, so often you end up gaining weight. The big problem is that your metabolism and your thyroid hormones are involved in your development. Hyperthyroidism can cause temporary delays. Hypothyroidism can cause more problems, but the degree of problems depends on the degree your hormones are out of balance. In both cases, however, the problems are reversible if the hormones are brought back into balance in a reasonable amount of time.

Hypothyroidism in an adolescent can cause weight gain; constipation; coarse, dry hair; and rough skin that may feel cool to the touch. You might not have all these symptoms or have them but only mildly. It is generally hyperthyroidism that causes sleeplessness, which is probably why your doctor first suspected it. As for development, hypothyroidism can slow down or delay your growth. Usually, once the hormones are balanced again, your development will resume. Strangely if you have hypothyroidism in childhood, it is strongly associated with puberty starting too early. This can lead to a reduced height because you go through adolescence too soon.

While your hormones are out of balance, hypothyroidism will cause problems with having erections and being fertile, so it will be something that you will need to monitor for the rest of your life. Fortunately, when the hormones are re-balanced, fertility is restored.

One thing to keep in mind is that sometimes the thyroid goes off for only a while and then recovers. I’ve also know people that have gone from being hyper to hypo.

Since your thyroid only seems to be a little bit out of whack, most likely it hasn’t greatly impacted your development. It is possible that what it was out of balance that it caused your development to pause. Your height can’t be a determining factor. There are too many variables involved. Just because you were always at the 50 percentile during childhood, it doesn’t necessarily follow that you will end up in the 50 percentile as an adult.

Stage four typically lasts two years. Yours might last a bit longer since your thyroid problem could have caused a slight delay. You were on the early side before, so this delay is not a big deal. You are now at about the average point for development from your description. During stage four you are likely to grow another one to two inches before you reach stage five. Facial hair starts developing in stage four, so nothing appears off in that regard. If you want to assess yourself, you can use the Tanner Stage of Development Calculator for Boys to get an estimate of where you are. If you would like me to review the information, you can send a copy of your answers with any comments or questions you might have.