TSH above 2.5 but below 4.0?

[giathinhpool]

This is my first time posting here. I read the guidelines and it seems like this topic is appropriate for a standalone post, so I hope this post is ok here. I am trying to conceive in my late 30s, and I have been sent to a fertility specialist. The fertility specialist noted that my TSH was around 3.4 earlier this year, so he had me go back and have it retested along with an antibody test. This time it was 2.74, and antibodies were in the normal range.

I went through my medical history and saw my TSH has always been between 2.4 and 3.8 since at least 2008. I have every single symptom of hypothyroidism starting in my late teens/early 20s, except for goiter (fatigue/brain fog, feeling cold, muscle and joint pain, irregular/heavy periods, etc). However, my GP says it's fibromyalgia, and doesn't think there are any issues with my thyroid.

I am reading mixed information about whether my TSH levels could potentially have an impact on my ability to get pregnant and have a healthy pregnancy. Some studies say that TSH must be below 2.5 during pregnancy, while others are saying there is no benefit of medicating anything under 4.0 during pregnancy. I've read about other women on this sub in this TSH range who took thyroid medication, but it's not clear whether it was necessary or beneficial. I am worried about the risks of unnecessarily medicating something that is not a problem.

Last week, my fertility specialist said that if he re-tested my TSH and it was still above 2.5, he wants to try to medicate it to get it below 2.5. But I'm not sure if it's really the right thing to do given that my TSH is not above 4.0 and is considered within a normal range. I especially don't want to do it if there are any risks. Should I get a second opinion? Should I ask for a full thyroid panel to see if anything is going on with my thyroid? Maybe I just have naturally slightly elevated TSH levels and it's totally normal and ok?

Did anyone else end up taking medication for TSH levels above 2.5 but below 4.0? And was do you feel that medicating the right choice for you? (don't say whether it resulted in pregnancy or not because that is against the rules, thank you. Maybe just whether there were any problems like side effects etc.)

Since it's possible that my fertility specialist will want to put me on medication to lower my TSH below 2.5, is there any difference in the types of thyroid medications they use? Are there certain medications that are safer or more effective for TTC/pregnancy?

 

[mcg1102]

@giathinhpool

Since it's possible that my fertility specialist will want to put me on medication to lower my TSH below 2.5, is there any difference in the types of thyroid medications they use? Are there certain medications that are safer or more effective for TTC/pregnancy?

The medication for hypothyroidism is just thyroid hormone in pill form, so there's not a huge variety of options (generally people are prescribed Synthroid/levothyroxine, which is just a pill version of the T4 thyroid hormone your body makes), and the safety profile is the same: the risk in medicating subclinical hypothyroidism is primarily in going too far the other way and causing hyperthyroidism.

In general, medicating thyroid levels between 2.5 and 4ish while TTC is done to be conservative, especially by REs in the context of fertility treatment, but there's not much evidence that it leads to beneficial outcomes, and it is certainly not necessary.

In their practice guidelines, the American Society for Reproductive Medicine concludes:

There is insufficient evidence that SCH (defined as TSH >2.5mIU/L with a normal FT4) is associated with infertility.There is fair evidence that SCH, defined as TSH levels >4mIU/L, is associated with miscarriage, but insufficient evidence that TSH levels 2.5–4 mIU/L are associated with miscarriage.There is fair evidence that treatment of SCH when TSH levels are >4.0 mIU/L is associated with improved pregnancy rates and decreased miscarriage rates... Given the limited data, if TSH levels prior to pregnancy are between 2.5 and 4 mIU/L, management options include either monitoring levels and treating when TSH >4 mIU/ L, or treating with levothyroxine to maintain TSH

 

[giathinhpool]

@mcg1102 That corresponds with what I have read too. I wasn't sure why they would medicate something that doesn't have a clear benefit, but if the risks of treatment are super low, and there's a tiny possibility of a benefit, that makes a little more sense. So I guess this means I could go either way. Given that I have almost every single symptom of hypothyroidism (which could just be fibromyalgia), maybe it would be worth trying since there are so few risks. Regardless, sounds like it would be a good idea to keep an eye on it, like the quoted practice guidelines say.

Thank you!

 

[called2greatness]

@giathinhpool You'll probably have to go on Synthroid. I'm on it and it has helped my levels. They are now a one point something.

 

[giathinhpool]

@called2greatness Thanks! Were your levels similar to mine (i.e., normal but not optimal)? Have you noticed any undesirable side effects?

 

[called2greatness]

@giathinhpool Mine were over 5. I was very tired and hairy. Now I am having less hair and my hormones overall are more desirable for ttc.

 

[thisisheavy]

@giathinhpool I started levothyroxine last December—my TSH for the last few years was ranging between 2-4 and I had symptoms. My PCP was never concerned even though I’d always been, but I decided to see a naturopath for hormone regulation in anticipation of TTC. She didn’t hesitate to put me on medication to get my TSH closer to 1. I have other fertility issues, but it’s nice to have eliminated a thyroid issue

 

[merry6]

@giathinhpool Hi there, I was in a similar position, mine was below 4.0 but above 2.5, can't remember the exact numbers. My RE put me on levothyroxine 0.025 mg, which I think is the lowest dose. I have been taking it since October 2021, no side effects, and I'm not as cold anymore! My RE repeated my tests in April to make sure my levels were not too low. If you are not comfortable taking it, you can always get a second opinion.

 

[giathinhpool]

@merry6 Thanks for sharing. They ended up letting me choose if I wanted to try it. They said my TSH is not dangerously high and it may not be necessary to lower it, but there's a chance it could help and the risks are low. (So basically they said the same thing I learned here.)

I have to admit the idea of my hands and feet not being ice cold all the time is appealing, and even better if it does help with fertility. So I have a prescription, and I am still considering and pros and cons. I haven't decided whether to try it or not. But I probably will.

 

[viviana]

@giathinhpool My doctors prefer TSH around 1 for trying to conceive. The issue with above 2.5 and below 4.0 might not play a huge role (although studies I’ve read suggest below 2.5) BUT your TSH levels can rise once pregnant. The rise can be significant and result in miscarriage. So having it under control to start, and monitoring throughout is the smart and prudent thing to do. There is nothing harmful with taking thyroid medication. And many benefits. It is totally possible to stop taking after having a baby. It is not something you become reliant on or need to take more of, necessarily. I have been taking it for almost 10 years and have remained on a very low dose. It is something my doctors consistently monitor.

 

[dens]

@giathinhpool I was on levothyroxine during my pregnancy with my 3 y.o. My levels were WAY above what is normal and I was having it checked my entire pregnancy. Then I ended up needing a higher dose even after pregnancy. It is so nice not having the night sweats anymore...those were my worse symptoms.