I am looking for some advice on my recent test results ahead of an appointment next week with an endocrinologist, to make sure I can fully maximise the contact time.
I am 30 weeks pregnant (I think the ranges are adjusted in pregnancy) and received the following results 2 weeks ago:
TSH: 3.59 (0.20 - 4.50)
Free T4: 5.6 (7.0 - 17.0)
I was enjoying a very active pregnancy until a month ago and now I feel very weak with extreme exhaustion. Although I am in my 3rd trimester, my symptoms feel beyond normal pregnancy fatigue. My GP was quite dismissive.
The test results also revealed low ferritin (14) and vit D (44) which I am now supplementing for.
Are there any relevant guidelines for normal TSH/low T4 that I could reference? Any questions/further investigations I should be asking for at my appointment?
Many thanks in advance.
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JacksonStreet
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I think the TSH can be lower in pregnancy & the range given is applied to your test as lab would be informed in notes what trimester you are currently in.
Your TSH is high in range & your FT4 is below range. Your FT3 also needs to be tested as this is the active thyroid hormone.
Ferritin very low did dr really dismiss it? & vitamin D. How much are you supplementing with?
Was B12 & folate tested? In range is not same as optimal. Add if you have.
Are you currently on any replacement? Has GP arrange referral or are you going private?
Have thyroid antibodies been tested? TPO & TG antibodies.
Hi PurpleNails , thank you very much for the reply.
Re ferritin - the GP said it was fine as in range (5-85) but I am already familiar with optimal ferritin ranges so started supplementing with ferrous sulphate 2-3x a day. The GP said I was fine to do this if I wanted to. I was prescribed a 2000IU daily vitamin D supplement, taken once daily. My B12 and folate were both in range (are these optimum levels though?)
B12 - 246 (145 - 910)
Folate - 16.8 (3.0 - 20.0)
Not sure if this is relevant, but my calcium (2.19, range 2.20-2.60) and albumin (24, range 35-50) were also out of range.
The endo referral is via the GP, 'to reassure me.' I am not taking any thyroid related drugs (is that what you meant by replacement?) and not had thyroid antibodies tested (something to ask at my appointment I guess...)
Thanks again for replying! I feel pretty horrendous but I am more worried about any negative effects on my unborn baby.
Hope someone more knowledgeable can confirm or correct me but by your stage of pregnancy your baby can make their own thyroid hormones.
In early pregnancy the baby uses your hormones & you need make more & use more to both support yourself & pregnancy so that can explain why your levels have likely dropped quite quickly.
I think when FT4 is below range you should be offered replacement hormone. When TSH is above 10 (overt hypothyroidism) replacement is offered. When it’s raised but under 10 it’s often repeated to ensure it’s not a once off.
Low nutrients can cause TSH to be lower than it should. Folate looks ok but B12 needs to be in top half - over 50% to be optimal.
Might be worth arranging a private blood test to repeat thyroid function with antibodies before appointment. That way if it shows similarly low levels you can push to start replacement hormone.
If your results show positive antibodies there a very strong argument to start replacement.
Medichecks offers an advanced thyroid including TPO & TG antibodies.
Monitor my health (MMH) offer an advance thyroid but only test TPO. (No TGab) but this is NHS lab so more accepted by doctors. Some do accept private results but often doctors prefer to ignore private tests altogether but the results gives you grounds to push for repeat testing.
There are companies & options, this page list them with discounts codes available.
For thyroid test for consistency it’s recommended you fast overnight, book draw for close to 09.00. Stop any supplements containing biotin 3 days before as biotin can skew results.
Low Vitamin D might be why calcium is borderline low, this will likely improve.
Ferritin below 30 should be investigated. Ferritin stores can be low but iron serum may not be. Doctor should have really done an iron panel.
by 11/12 weeks gestation the fetus has grown it's own thyroid and starts making it's own T4/T3.
The critical period when untreated hypothyroidisim affects the neuro -development of the fetus is during the first 4/5/6 weeks (before it has it's own supply) ,and as you felt reasonably well , it a reasonable assumption that you had 'enough ' thyroid hormone for both of you at that point .
So try not to worry ... low T4 is quite likely to make you feel rubbish at the moment . but baby is happily making it's own and has been for months .
Hypothyroidism would not be diagnosed or treated at this stage in a pregnancy unless the TSH was over range , (and even then, it would need to still be over range on a repeat test at least a month later , usually 3 months later.
Yours isn't, which is why GP was not concerned , but the fact that your fT4 is actually below range does complicate the picture a bit , so it's good you are going to see someone about it.
However since you are at such a late stage of pregnancy, i'd be very surprised if they suggested anything other than watch and wait at the moment.
Pregnancy induces it's own changes in the quantities of thyroid hormones produced , and alterations in the ratio of Free T4 to Total T4 (which includes T4 that is 'bound' to thyroid binding globulins which transport it round in the blood).
The levels of thyroid binding globulins are increased because the blood volume is significantly increased over the course of the pregnancy ..... so i wonder if this may possibly account for your Free T4 being low currently ..more of it may be bound to higher leve's of TBG's ..... so your Total T4 level may be absolutely fine ..., perhaps ask the endo about this ,and perhaps ask for a Total T4 for reassurance ?
Also Thyroid hormones often go a bit wonky in the months following a birth , often only temporarily (as a result of the system rebalancing itself back to non-pregnant state) , but sometimes these problems turn into permanent hypothyroidism ,(especially when levels of Thyroid antibodies are high ).
bearing all these current and upcoming changes that are to be expected during after pregnancy in mind , diagnosing/ treating hypothyroidism at this stage would be very tricky.
Because after you give birth your system will begin the process of adjusting itself back to 'non pregnant' .
You and your GP should certainly be keeping an eye on your results though ,
I became hypothyroid (during ?) or after a pregnancy , i was absolutely exhausted during the whole pregnancy from day 1,.....no tests done .. then felt great for about 2 weeks before the birth and fro a few weeks after .
Sometime during the first year i had a couple of months that (with hindsight) was probably a mildly hypErthyroid stage .. and then i gradually got slower/ more tired/ and colder over the next couple of years until somebody finally though to test me for hypothyroidism and i was diagnosed / treated .
So it's good you are 'on the case' already .. but don't worry about your baby .. it will be fine with it's own supply of T4 /T 3 even it you feel like you are wading though mud all day at the moment.
Babies do have a tendency to take what they need to survive ~ at your expense .
I felt absolutely godawful from week one ... but that baby is now 30 something and has been capable of making broken engines and computers work since the age of about 7,,and thinks elecrotonics are 'obvious ' and has never understood why the rest of us struggle to get out heads round them ... so his neuro development didn't seem to come to any harm despite how horribly exhausted i felt in the first weeks when he hadn't even got a thyroid of his own ( he was a bit slow to come round round at birth , and a bit yellow , but he was absolutely fine after 48hrs )
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