Thyroid UK
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Period 5 days late...pregnant or Thyroid

Hello all,

I was diagnosed Hypothyroid in October. I was put on 50mcg of Levothyroxin which was upped to 75mcg in November. My last TSH reading was 0.91, which has dropped from 7.35.

My fiancé and I were due to start IVF in February but decided to give it 'one last go' in December. I am now 5 days late.

I've had period cramps, tender breasts and have been a bit emotional - all like my period was about to show.

I've taken 2 Clearblue pregnancy tests this morning which were both negative. I've read that Hypothyroidism can make periods late or even stop them altogether, but surely I wouldn't have period symptoms or feel like I was going to come on if the hypothyroid was making me late/stopping my periods...

If anyone can help or shed any light on this, that would be great. If anyone has had similar experiences, it would be great to know what happened.

15 Replies
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NeensB,

Untreated hypothyroidism can interrupt your menstrual cycle and stop periods but your TSH 0.91 is euthyroid (normal) so it's unlikely that your late period is due to hypothyroidism.

I would do another pregnancy test in a few days. If you are pregnant Levothyroxine dose should be increased by 25mcg-50mcg to ensure good foetal development. NICE also recommends that hypothyroid women planning conception should be referred to endocrinology for management. cks.nice.org.uk/hypothyroid...

The BTA recommend that the TSH should be 0.4-2.5 during the first trimester.

Management of primary hypothyroidism: statement by the British Thyroid Association Executive Committee

The serum TSH reference range in pregnancy is 0·4–2·5 mU/l in the first trimester and 0·4–3·0 mU/l in the second and third trimesters or should be based on the trimester-specific reference range for the population if available. These reference ranges should be achieved where possible with appropriate doses of L-T4 preconception and most importantly in the first trimester (1/++0). L-T4/L-T3 combination therapy is not recommended in pregnancy (1/+00).

onlinelibrary.wiley.com/doi...

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Thank you so much for your reply. As I've been having period like symptoms I didn't think that it was the Hypothyroidism causing the issue as I imagine that if that were the case, I'd have no symptoms. My cycles are pretty regular and I have never had a cycle lasting this long. I did wonder if the Levo or the hypo could make the tests negative, even if they are positive.

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NeensB,

I can't see how Levothyroxine or being hypothyroid can affect the pregnancy tests.

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It all seems very odd. Since starting Levo I have had 2 periods that were completely normal.

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NeensB,

So it is unlikely that Levothyroxine is causing the late period. Perhaps you are pregnant and the tests were wrong?

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I really hope so! Going to wait another day or two and then maybe take a different test...

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Some women don't produce sufficient hCG in early pregnancy so can have negative pregnancy tests for up to 8 weeks.

Standard advice tends to be wait another 5-7 days and if you haven't had a "normal" period by then retake the test and if it is still negative go then go to see your GP.

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Thank you. That's exactly what I think I will do.

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Hello there

My periods stopped around this time last year and are still not right..in the end this was one of the biggest symptoms for me...I would either literally miss a whole month or then the following month have horrific painful breasts for two weeks before I was due, extremely heavy bleeding and very clotted which I thought was the early onset of perimenopause which delayed me getting diagnosed until August this year

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I didn't have a thyroid problem at the time but pregnancy test I think we're negative for all my children first time of testing. I remember once going back I got the same tester I had earlier you told me it was now positive and she had thought that was the case the first time as I was a long time before it said negative! The cut off though has to be at a higher level I suppose as it would be terrible to be told positive when it wasn't.

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I got sore breasts, strong period like cramps on my right side and diarrhea when I was pregnant all before my period was due. Also very tired. Good luck!!

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Thank you so much. Now you mention it, I too had one attack of diarrhoea on Christmas Eve. Nothing since then. Now 6 days late. Still no period.

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hmmm, have my fingers crossed for you, your symptoms are promising, especially now since you are being treated and have a normal TSH! TSH over 2.5 can cause infertility yet doctors don't want to treat non pregnant people with a TSH under 10, isn't that a joke?

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It's a complete joke. Mine was ignored for a while - misdiagnosed at first as CFS.

We were meant to start IVF in February and this was our last go...never ever had a period this late before so hoping that this could be good news. Read about some ladies not getting a positive test until they were 2 weeks late so hoping something like that may happen to me!

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Pretty much every time I increase my dose of Levo my next period is late, then it settles back into it's usual pattern, but I have also heard of people who did not get pregnant until they were properly medicated - so lets keep or fingers crossed it's the latter! Either way, bringing your TSH down should have helped.

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