Hypothyroidism and Miscarriage

We have discussed how most cases of sub-clinical hypothyroidism (SCH) do not require treatment with thyroid hormone. However, there is one notable exception – pregnancy. High level scientific evidence suggests that treating SCH can reduce the risk of miscarriage. Let’s discuss.

Dr. R’s Fast Facts

Patients with subclinical hypothyroidism before 20 weeks of pregnancy have a higher risk of miscarriage: Trusted SourcePubMedGo to source A systematic review and meta-analysis.

  • Reviewed 9 high quality studies.
  • Subclinical hypothyroid increases chance of miscarriage.
    • Subclinical hypothyroid = high TSH (over 4.5) and normal T4.
  • SCH and thyroid autoimmunity increases risk even more.
  • Women who were treated for SCH with thyroid hormone had the same risk of miscarriage as healthy controls.
  • “…we recommend early treatments to avoid adverse pregnancy outcomes and complications.”
  • What to do:
    • Make sure you are regularly screened for thyroid health if you are trying to get pregnant and during your pregnancy.

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Hypothyroidism and Miscarriage

Dr. Michael Ruscio: Hi, this is Dr. Ruscio. And let’s discuss the association between your thyroid and miscarriage. And certainly something—miscarriage, that is something that we want to avoid and is something that if there’s anything that we can do to screen for an increased risk and potentially understand what treatments may help decrease the risk of miscarriage, that’s truly something that we want to do.

So the paper Trusted SourcePubMedGo to source I’d like to discuss with you is a systematic review with meta-analysis. And I’ll put the abstract up here on the screen. And as we’ve discussed before, a systematic review with meta-analysis essentially reviews all of the high quality available data. And in this case, nine studies, nine high quality studies were reviewed looking at the association between subclinical hypothyroidism and miscarriage.

And they found that those with subclinical hypothyroidism were at increased risk of miscarriage. They also found that having subclinical hypothyroidism and having thyroid autoimmunity increase your risk even more. Now, a subclinical hypothyroidism is when your TSH is elevated above 4.5 and your T4 is normal. What’s comforting about this study is that women who were treated for subclinical hypothyroidism with thyroid hormone had a risk of miscarriage equivalent to that of healthy controls. So certainly there’s a very viable treatment if you do find this elevated TSH with normal T4, subclinical hypothyroidism.

So what to do? If you are trying to get pregnant or pregnant or have had a history of miscarriage, make sure to have a thyroid screening. And if you are subclinical hypothyroid, speak with your doctor about undergoing thyroid hormone replacement treatment, because, clearly, this systematic review with meta-analysis, very high quality level data, has shown that being subclinical hypothyroid, and especially if you have subclinical hypothyroid and you’re thyroid autoimmunity, or thyroid autoimmune, you have an increased risk of miscarriage, which can be nullified or at least improve to that of the level of healthy controls when taking thyroid hormone.

So this is Dr. Ruscio, and I hope this information helps you get healthy and get back to your life. Thanks.

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