change in size

[tiredpoet]

Does the normal thyroid change in size?  
To date all my TSH has been in a normal range and I am not now nor have I ever been treated for a thyroid disorder.
Sometimes my thyroid feels "enlarged," and hard as a rock. I saw an endocrinologist some time back who described it as "prominent." Other times it doesn't feel quite so prominent. (I am extremely small, with a very small, thin neck, so any tiny growth is evident.)
Earlier this year my thyroid felt particularly prominent and even my PC noted it felt very hard and fixed.  I was having some odd symptoms, such as rapidly thinning hair, but my TSH was good (1.17).  An u/s of my thyroid noted that it was not enlarged.  This was the first u/s of my thyroid I'd ever had done.  Could that have meant that it wasn't enlarged by medical standards, but could it still have been larger than my normal thyroid size?

I had repeat u/s recently, so it's been about 8 or 9 months, and my thyroid felt less prominent and the ultrasound showed that it was smaller than on the first u/s.  (I can't remember the exact numbers.  On both ultrasounds the right side was a bit larger than the left - and has a small 6mm nodule - but for example one side went from 5.1cm in length to 3.7cm.  It was 5.1 cm when it felt prominent and hard - now it feels okay and is 3.7cm.  I am sure, based on past experience, that at some point in the next few months it will start to feel bigger again.   5.1 is still a normal sized thyroid, though I'm wondering if for me that's enlarged.)

These aren't very significant changes in size, but I'm just wondering: Is it a normal occurrence for a normal-functioning thyroid to change size periodically (possibly due to hormonal shifts, diet, etc)?  As I said, I am not on any thyroid medication and never have been.  I was up until very recently on birth control pills, but other than that my diet is very consistent and I am not taking any other medications.

[Mark Lupo, M.D.]

Sometimes hashimoto's and graves can have a firm thyroid.
The length on ultrasound measurement of the thyroid is user-dependent and tends to vary from study to study, would not read so much into this.

[tiredpoet]

Thanks - and thank you for being so great about answering these questions.  It's so appreciated!

My mother had Graves.  I at times have a few symptoms (intolerance to heat, increased sweating, change in menstrual cycle) but they're not extreme and could be attributed to other causes - also, I have been prescribed Adderall (adderrall) to help me stay awake during the day, so it seems many symptoms of Graves would almost mimic side effects of Adderall (adderrall).  

A few years ago when I first started having symptoms an endocrinologist suggested Hashimoto's - before he ran any tests.  My test results at the time came back normal - TSH was 2.1 and some other levels were off, but he said that was most likely due to my being on birth control pills.  My thyroid was described at that time as "very prominent" but we didn't do an ultrasound.  

The symptoms of Hashimoto's fit me to a T - in fact the first time I read about it I nearly cried thinking finally, this is everything I've been trying to explain.
Aside from weight gain - 4 years ago I gained approx 15 pounds for no reason and it will not come off, but I haven't gained any weight since then and I'm still at a very healthy weight of 115 lbs at 5'3".

My voice gets hoarse every single day.  My once extremely thick hair has been rapidly thinning and becoming dry.  I have extreme muscle weakness, particularly in my legs. My muscles always ache as if they've been overworked. My feet swell up to a frightening degree.  My face often gets puffy and looks like it's retaining water.  In fact, I retain so much water all the time for no reason.  (I was put on the diuretic spironolactone for a brief period last year and lost literally 12 pounds, which I'm assuming was water, that I put right back on as soon as I was taken off the drug). I have relentless fatigue and terrible brain fog. My skin is pale and even though I have problems with acne on my face the rest of my body tends to get extremely dry.  I always feel constipated, and I am extremely intolerant to cold - and even when it's not that cold my fingers stiffen up so badly I literally can't even move them.

As you can see, since most everything else has been ruled out, on paper at least it looks like Hashimoto's could be the root of my problems.  But when all these symptoms first started my TSH was normal at 2.1 and the antibody test was negative.

Since then I have had my TSH retested a few times, and it's always been normal and in fact has become pretty optimal (went from 2.1 in 2005 to 1.79 in 2006  to 1.17 in 2008.  Was just tested recently and I don't know the level but I was told it was normal).  

My thyroid seems to go from extremely prominent and feeling like it's hard as a rock to feeling less prominent and hard, then back to more prominent, over and over.  But u/s showed it is not enlarged and there's only one small nodule on the right side.

I think I've read that a small percentage of people with Hashimoto's will have normal TSH, but would they also have normal sized thyroid and not have multiple nodules, etc?  Is there any reason for a thyroid to mildly swell up intermittently?

I had the antibody test 4 years ago when I first started experiencing symptoms and it was negative, but symptoms have persisted unexplained for several years.  Would it be worth testing antibodies again, even with normal TSH and no enlargement of thyroid?  

Also, I am off birth control pills now.  Would doing a full thyroid panel now be more accurate?