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Can someone help with my lab results? TSH low, free T3 and T4 normal range.
I am 37 years old and about 16 weeks pregnant. When I had my first set of prenatal labs, my TSH came back as low at 0.0643. They called me back in to do a thyroid panel, and I just got my results back which were TSH 0.092, free T3 3.6, and free T4 0.95. The nurse made note that T3 and T4 were in normal range, but TSH is "very low" and they referred me to maternal fetal medicine. The doctor's note says "may need small dose of Synthroid."
I am very confused now. Doesn't a low TSH mean HYPERthyroidism? And wouldn't Synthroid be for HYPOthyroidism? I am finding so much conflicting information online, and I have to wait until my appointment on the 21st to get an answer on all this. Of course, it's all making me very nervous. Can someone help explain or shed some light on my lab results as far as what they could mean? I was seeing that a lower-ish T4 and low TSH can actually indicate hypo, so I'm really confused now. Thanks in advance!
I am very confused now. Doesn't a low TSH mean HYPERthyroidism? And wouldn't Synthroid be for HYPOthyroidism? I am finding so much conflicting information online, and I have to wait until my appointment on the 21st to get an answer on all this. Of course, it's all making me very nervous. Can someone help explain or shed some light on my lab results as far as what they could mean? I was seeing that a lower-ish T4 and low TSH can actually indicate hypo, so I'm really confused now. Thanks in advance!
Well, we kind of have a mishmash of FT3 and total T3 and FT4 and total T4. But, if you look at where you were in the ranges before getting pregnant, you will see that TT3 was almost exactly where FT3 is now (midrange). Your TT4 in September was 48% of range, which is quite a lot higher than your FT4 now (16%) and right there close to the 50% guideline. However, we have to keep in mind that total and free tests are not directly comparable. Have all your symptoms started since the September labs?
If your doctor suspects an autoimmune disease, he should be testing the markers for autoimmune thyroid disease, which are TPOab (thyroid peroxidase antibodies) and TGab (thyroglobulin antibodies), which are the markers for Hashimoto's thyroiditis, and TSI (thyroid stimulating immunoglobulin), which marks Graves'.
I think you will find all of this a bit less confusing if you ignore your TSH. TSH is a pituitary hormone, a messenger from your pituitary to your thyroid to tell it to produce more hormone. TSH, either low or high, causes NO symptoms. If you concentrate on what has changed, I think it's obvious that your very much lower T4 level is a prime suspect. Perhaps the answer is as simple as your thyroid is currently producing for two.
If your doctor suspects an autoimmune disease, he should be testing the markers for autoimmune thyroid disease, which are TPOab (thyroid peroxidase antibodies) and TGab (thyroglobulin antibodies), which are the markers for Hashimoto's thyroiditis, and TSI (thyroid stimulating immunoglobulin), which marks Graves'.
I think you will find all of this a bit less confusing if you ignore your TSH. TSH is a pituitary hormone, a messenger from your pituitary to your thyroid to tell it to produce more hormone. TSH, either low or high, causes NO symptoms. If you concentrate on what has changed, I think it's obvious that your very much lower T4 level is a prime suspect. Perhaps the answer is as simple as your thyroid is currently producing for two.
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Thank you so much for your help!
I have just about every hypo symptom there is listed, but I also have several hyper symptoms as well (very high anxiety, faster than normal heart rate, trouble sleeping).
I have been diagnosed with PCOS for 14 years and have a "classic" case of that as far as my labs and health have gone. I have been told over the past few years that I have "some kind of autoimmune disorder" although it has never been pinpointed. I did have a raised rheumatoid factor a few years ago on a blood panel I had done, but the doctor told me not to worry about it. My PCP tests my thyroid every year because he swears a lot of my problems are thyroid related, but my last panel done on September 5, 2015 (about 2 weeks before I became pregnant) was: TSH 0.69 (reference 0.45 to 4.5), T4 8.1 (reference range 4.5 to 12), T3 uptake (%) 30 (reference range 24-39, free T4 index 2.4 (reference range 1.2 to 4.9), and T3 125 (range of 71-180). I was told that again my TSH was on the low end of normal (as it is every time they test it, but it was perfectly normal and fine. Then I had the initial TSH reading when I had my first pregnancy workup at the end of November, which was 0.0643, which prompted the next thyroid panel, taken the last week of December with the above findings. This is sooooo entirely confusing to me!
I have been diagnosed with PCOS for 14 years and have a "classic" case of that as far as my labs and health have gone. I have been told over the past few years that I have "some kind of autoimmune disorder" although it has never been pinpointed. I did have a raised rheumatoid factor a few years ago on a blood panel I had done, but the doctor told me not to worry about it. My PCP tests my thyroid every year because he swears a lot of my problems are thyroid related, but my last panel done on September 5, 2015 (about 2 weeks before I became pregnant) was: TSH 0.69 (reference 0.45 to 4.5), T4 8.1 (reference range 4.5 to 12), T3 uptake (%) 30 (reference range 24-39, free T4 index 2.4 (reference range 1.2 to 4.9), and T3 125 (range of 71-180). I was told that again my TSH was on the low end of normal (as it is every time they test it, but it was perfectly normal and fine. Then I had the initial TSH reading when I had my first pregnancy workup at the end of November, which was 0.0643, which prompted the next thyroid panel, taken the last week of December with the above findings. This is sooooo entirely confusing to me!
Your FT4 is only at 16% of range, which is low. FT3 and FT4 reference ranges are very flawed, and many of us believe the whole bottom half of the range (anything less-than 50%) should probably be considered hypo. FT3 is in the upper half of the range, which is right where it should be. It's most likely your FT3 level that's keeping your TSH so low.
Are you having any hypo or hyper symptoms? I know pregnancy complicates determining that.
Are you having any hypo or hyper symptoms? I know pregnancy complicates determining that.
It is confusing, especially since TSH is counterintuitive. The lower TSH is, the higher the thyroid function and vice versa. However, TSH is a pituitary hormone, and it can be unreliable in diagnosing thyroid status. FT3 and FT4 are much more reliable.
Please post the reference ranges for your FT3 and FT4. Ranges vary lab to lab and have to come from your own lab report.
Synthroid is for hypothyroidism. I can see, even without a reference range, that your FT4 is low. Your doctor's comment is appropriate.
I'll comment further once I see the ranges.
Please post the reference ranges for your FT3 and FT4. Ranges vary lab to lab and have to come from your own lab report.
Synthroid is for hypothyroidism. I can see, even without a reference range, that your FT4 is low. Your doctor's comment is appropriate.
I'll comment further once I see the ranges.
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